To properly assign the queue to the `ConsumeOkEvent`, we need perform
such a logic in the `Consumer.handleConsumeOk()`.
* Introduce `BlockingQueueConsumer.ConsumerDecorator` to be created on
each `channel.basicConsume()` for wrapping the target `InternalConsumer`
per queue
* Add getters to the `ConsumeOkEvent` for better interoperability
* Assert assigned queue names for the `ConsumeOkEvent`s in the
`SimpleMessageListenerContainerIntegration2Tests`
**Cherry-pick to 1.7.x**
* Add `ConsumerDecorator.consumerTag` property
* Add `ConsumerDecorator.toString()`
* Add JavaDocs for the `ConsumeOkEvent`
