fix more broken tests;

Signed-off-by: Stefan Maute <stefan.maute@bosch.io>

thingsearch/service/src/test/java/org/eclipse/ditto/thingsearch/service/persistence/AbstractThingSearchPersistenceITBase.java

@@ -114,6 +114,7 @@ private MongoThingsSearchPersistence provideReadPersistence() {
         final MongoThingsSearchPersistence result = new MongoThingsSearchPersistence(mongoClient, actorSystem, config);
         // explicitly trigger CompletableFuture to make sure that indices are created before test runs
         result.initializeIndices().toCompletableFuture().join();
+
         return result;
     }
 
@@ -201,6 +202,7 @@ protected ResultList<ThingId> findAll(final Query query, final List<String> subj
 
     protected <T> T runBlockingWithReturn(final Source<T, NotUsed> publisher) {
         final CompletionStage<T> done = publisher.runWith(Sink.last(), actorSystem);
+
         return done.toCompletableFuture().join();
     }
 

thingsearch/service/src/test/java/org/eclipse/ditto/thingsearch/service/persistence/read/SortingIT.java

@@ -232,7 +232,7 @@ private <E> List<Thing> createAndPersistThings(final Collection<E> values, final
 
         final List<Thing> things = values.stream()
                 .map(builderFunction)
-                .toList();
+                .collect(Collectors.toList()); // do not replace with .toList()
         // shuffle the documents for more realistic testing
         Collections.shuffle(things);
         things.forEach(this::persistThing);