813d86e5e0
If a `MessageConverter` bean is available, we now associate it to the created `RabbitTemplate` and `RabbitListenerContainerFactory`. That way, registering a custom `MessageConverter` is all that's needed. The Rabbit auto-configuration is now using the new `ObjectProvider` that offers a nicer API to detect if a primary candidate is available for optional collaborators. Closes gh-5088