`MessageConverter` failures stall processing indefinitely with manual/post-processing acknowledgment

[kdubb]

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If a MessageConverter.convert(...) method throws an exception, the incoming channel is stalled indefinitely; exceptions are logged but nothing else happens.

This is being experienced specifically with RabbitMQ but it appears this might affect any broker.

[kdubb]

I've edited the issue to reflect that this is happening with manual & post-processing ack strategies.