Fix Reference Resolution on Extended Primitive References

[astruebi]

Happens in the latest build, which runs on WSL Ubuntu for me. When uploading the newly generated Polar test data, nothing is uploaded and the following error occurs:

`C:\Users\Ich>blazectl --server http://localhost:8082/fhir upload "G:\Projekte\smith\TestDataGenerator\outputGlobal" -c 2
Starting Upload to http://localhost:8082/fhir ...
Inspecting files eligible for upload from G:\Projekte\smith\TestDataGenerator\outputGlobal... DONE
Found 1 bundles in total (from 1 JSON files and from 0 NDJSON files)
Uploads          [total, concurrency]     1, 2
Success          [ratio]                  0.00 %
Duration         [total]                  85ms
Requ. Latencies  [mean, 50, 95, 99, max]  77ms, 77ms, 77ms, 77ms 77ms
Bytes In         [total, mean]            10.25 KiB, 10.25 KiB
Bytes Out        [total, mean]            634.31 KiB, 634.31 KiB
Status Codes     [code:count]             200:0, 500:1

Non-OK Responses:

File: G:\Projekte\smith\TestDataGenerator\outputGlobal\POLAR_Testdaten_Original_UKB-UKB-0001.json [Bundle: 1]
    StatusCode  : 500
    Severity    : Error
    Code        : An unexpected internal error has occurred.
    Diagnostics :                                                                      java.lang.Thread.run                  Thread.java:  833
                                    org.eclipse.jetty.util.thread.QueuedThreadPool$Runner.run        QueuedThreadPool.java: 1034
                                        org.eclipse.jetty.util.thread.QueuedThreadPool.runJob        QueuedThreadPool.java:  883
                      org.eclipse.jetty.util.thread.ReservedThreadExecutor$ReservedThread.run  ReservedThreadExecutor.java:  409
                                    org.eclipse.jetty.util.thread.strategy.EatWhatYouKill.run          EatWhatYouKill.java:  131
                             org.eclipse.jetty.util.thread.strategy.EatWhatYouKill.tryProduce          EatWhatYouKill.java:  173
                              org.eclipse.jetty.util.thread.strategy.EatWhatYouKill.doProduce          EatWhatYouKill.java:  315
                                org.eclipse.jetty.util.thread.strategy.EatWhatYouKill.runTask          EatWhatYouKill.java:  338
                                                   org.eclipse.jetty.io.ChannelEndPoint$1.run         ChannelEndPoint.java:  104
                                                   org.eclipse.jetty.io.FillInterest.fillable            FillInterest.java:  105
                               org.eclipse.jetty.io.AbstractConnection$ReadCallback.succeeded      AbstractConnection.java:  311
                                           org.eclipse.jetty.server.HttpConnection.onFillable          HttpConnection.java:  277
                                                  org.eclipse.jetty.server.HttpChannel.handle             HttpChannel.java:  479
                                                org.eclipse.jetty.server.HttpChannel.dispatch             HttpChannel.java:  732
                                         org.eclipse.jetty.server.HttpChannel.lambda$handle$1             HttpChannel.java:  487
                                                       org.eclipse.jetty.server.Server.handle                  Server.java:  516
                                       org.eclipse.jetty.server.handler.HandlerWrapper.handle          HandlerWrapper.java:  127
    ring.adapter.jetty.proxy$org.eclipse.jetty.server.handler.AbstractHandler$ff19274a.handle
                                                    ring.adapter.jetty/async-proxy-handler/fn                    jetty.clj:   59
                                                                  blaze.server/wrap-server/fn                   server.clj:   22
                                                                                          ...
                                                                  reitit.ring/ring-handler/fn                    ring.cljc:  339
                                                    blaze.rest-api.middleware.log/wrap-log/fn                      log.clj:   18
                                                                                          ...
                                                  blaze.rest-api.middleware.cors/wrap-cors/fn                     cors.clj:   12
                                                                  reitit.ring/ring-handler/fn                    ring.cljc:  338
                                                                        reitit.ring/routes/fn                    ring.cljc:  122
                                                                      reitit.ring/routes/fn/f                    ring.cljc:  120
                                                        ring.middleware.params/wrap-params/fn                   params.clj:   77
                                              blaze.rest-api.middleware.output/wrap-output/fn                   output.clj:  102
                                                    blaze.middleware.fhir.error/wrap-error/fn                    error.clj:    9
                                        blaze.rest-api.middleware.forwarded/wrap-forwarded/fn                forwarded.clj:   37
                                                                  blaze.rest-api.routes/fn/fn                   routes.clj:   61
                                          blaze.rest-api.middleware.resource/wrap-resource/fn                 resource.clj:  106
                                blaze.rest-api.middleware.batch-handler/wrap-batch-handler/fn            batch_handler.clj:    6
                               blaze.middleware.fhir.metrics/wrap-observe-request-duration/fn                  metrics.clj:   52
                                       blaze.interaction.transaction/wrap-interaction-name/fn              transaction.clj:  522
                                                     blaze.interaction.transaction/handler/fn              transaction.clj:  513
                                                                blaze.async.comp/then-compose                     comp.clj:  200
                                           java.util.concurrent.CompletableFuture.thenCompose       CompletableFuture.java:  144
                                           java.util.concurrent.CompletableFuture.thenCompose       CompletableFuture.java: 2309
                                       java.util.concurrent.CompletableFuture.uniComposeStage       CompletableFuture.java: 1187
                                                                blaze.async.comp//reify/apply                     comp.clj:  161
                                                  blaze.interaction.transaction/handler/fn/fn              transaction.clj:  516
                                                                                          ...
                                                   blaze.interaction.transaction/eval41959/fn              transaction.clj:  483
                                                                        blaze.db.api/transact                      api.clj:   62
                                                                blaze.db.node.Node/-submit-tx                     node.clj:  254
                                                        blaze.db.node.transaction/prepare-ops              transaction.clj:   80
                                                                            clojure.core/mapv                     core.clj: 6970
                                                                          clojure.core/reduce                     core.clj: 6885
                                                                                          ...
                                                                         clojure.core/mapv/fn                     core.clj: 6979
                                                                      clojure.core/partial/fn                     core.clj: 2641
                                                                                          ...
                                                       blaze.db.node.transaction/eval23580/fn              transaction.clj:   36
                                                              blaze.fhir.spec.type/references                     type.clj:   66
                                                blaze.fhir.spec.type.protocols/eval11095/fn/G                protocols.clj:    4
                                                            blaze.fhir.spec.type/eval16903/fn                     type.clj: 1106
                                                                       clojure.core/transduce                     core.clj: 6947
                                                                  clojure.core.protocols/fn/G                protocols.clj:   13
                                                                    clojure.core.protocols/fn                protocols.clj:   75
                                                           clojure.core.protocols/iter-reduce                protocols.clj:   49
                                                                       clojure.core/map/fn/fn                     core.clj: 2759
                                                blaze.fhir.spec.type.protocols/eval11095/fn/G                protocols.clj:    4
                                                            blaze.fhir.spec.type/eval16859/fn                     type.clj: 1073
                                                                          clojure.core/reduce                     core.clj: 6885
                                                                                          ...
                                                         blaze.fhir.spec.type/eval16859/fn/fn                     type.clj: 1073
                                                blaze.fhir.spec.type.protocols/eval11095/fn/G                protocols.clj:    4
                                                            blaze.fhir.spec.type/eval16903/fn                     type.clj: 1106
                                                                       clojure.core/transduce                     core.clj: 6947
                                                                  clojure.core.protocols/fn/G                protocols.clj:   13
                                                                    clojure.core.protocols/fn                protocols.clj:   75
                                                           clojure.core.protocols/iter-reduce                protocols.clj:   49
                                                                       clojure.core/map/fn/fn                     core.clj: 2759
                                                blaze.fhir.spec.type.protocols/eval11095/fn/G                protocols.clj:    4 (repeats 2 times)
                                                   blaze.fhir.spec.type.Reference/-references                     type.clj: 1212
                                                     blaze.fhir.spec.type/reference-reference                     type.clj: 1199
                                                                         clojure.string/split                   string.clj:  219
    java.lang.ClassCastException: class blaze.fhir.spec.type.ExtendedString cannot be cast to class java.lang.CharSequence (blaze.fhir.spec.type.ExtendedString is in unnamed module of loader clojure.lang.DynamicClassLoader @62b92df8; java.lang.CharSequence is in module java.base of loader 'bootstrap')`

POLAR_Testdaten_Original_UKB-UKB-0001.zip