Fix "Expected value reference of type STRING but got PARAMETER" Excep…

…tion when using a parameter for a stream title (#20244)

StreamReferenceFacade uses asString() without parameter mapping when retrieving the stream title from a content pack. This leads to the aforementioned Exception, while installing a content pack containing a stream title with attached parameter.

graylog2-server/src/main/java/org/graylog2/contentpacks/facades/StreamReferenceFacade.java

@@ -144,7 +144,7 @@ public NativeEntity<Stream> createNativeEntity(Entity entity,
 
     private Optional<NativeEntity<Stream>> findExisting(EntityV1 entity, Map<String, ValueReference> parameters) {
         final StreamReferenceEntity streamEntity = objectMapper.convertValue(entity.data(), StreamReferenceEntity.class);
-        final List<Stream> streams = streamService.loadAllByTitle(streamEntity.title().asString());
+        final List<Stream> streams = streamService.loadAllByTitle(streamEntity.title().asString(parameters));
         if (streams.size() == 1) {
             final Stream stream = streams.get(0);
             return Optional.of(NativeEntity.create(entity.id(), stream.getId(), ModelTypes.STREAM_V1, stream.getTitle(), stream));