Fix rabbitmq docker image build

.github/workflows/rabbitmq-oci.yaml

@@ -79,9 +79,20 @@ jobs:
         working-directory: rabbitmq-server
         run: |
           sed -i"_orig" -E '/APP_VERSION/ s/3\.[0-9]+\.[0-9]+/${{ steps.load-rabbitmq-info.outputs.RABBITMQ_SHA }}/' rabbitmq.bzl
+          RULES_ERLANG_VERSION=$(bazelisk query --output=build //external:rules_erlang  | sed -r -n 's/^.*tag = "(.*)".*$/\1/p')
           bazelisk build :package-generic-unix \
             --config=rbe-${{ matrix.otp_major }} \
-            --override_repository rules_erlang~3.9.9~erlang_package~osiris=${{ github.workspace }}/osiris
+            --override_repository rules_erlang~$RULES_ERLANG_VERSION~erlang_package~osiris=${{ github.workspace }}/osiris
+
+          # rules_erlang version detection is not bullet-proof, so let's check that override did indeed work
+          set -o pipefail
+          if ! tar --list -f ./bazel-bin/package-generic-unix.tar.xz  | grep -F "plugins/osiris-${{ github.event.pull_request.head.sha || github.sha }}/ebin/osiris.app" ; then
+            echo "Failed to override osiris repo"
+            echo "Inferred repo name: rules_erlang~$RULES_ERLANG_VERSION~erlang_package~osiris"
+            echo "Repo name as seen after build:"
+            ls bazel-bin/external/ | grep osiris
+            exit 1
+          fi
 
       - name: Resolve generic unix package path
         run: |