3rd-party dependency for app starters

[braindrain]

After migration of router-sink 2.1.5.RELEASE to version 3.0.2, the issue of converting payload appeared:
java.lang.IllegalArgumentException: Payload must not be null.

The input message content-type is application/*+avro

It's caused by attempt of spring-router 3.0.2 to call appropriate (Avro) Payload input converter (consumer.key/value-deserializer, producer.key/value-serializer). But it's not in classpath of spring-router. We need to add 3rd party dependency (Avro) to the app starter.

There's an option of patching the app with new dependencies: https://docs.spring.io/spring-cloud-stream-app-starters/docs/current/reference/html/_introduction.html#_patching_pre_built_applications, however https://start-scs.cfapps.io/ is not accessible.

What's the preferred approach?