Fix a potential race condition between channel recovery and acknowledgement offset

[vikinghawk]

Proposed Changes

We encountered recovery errors during a brief network outage for a slow consumer that was under heavy load. When attempting to acknowledge a delivery the channel was closed with
reply-code=406, reply-text=PRECONDITION_FAILED - unknown delivery tag 0, class-id=60, method-id=80) and messages stopped being delivered.

I was able to create a test app to easily recreate the issue. After these changes I could not recreate.

Changes are:

1. Don't allow sending an ack with tag=0 unless multiple=true. Reading thru the AMQP spec, 0 should only ever be valid when using multiple.
2. Fix potential timing issue by inheriting the offset on the new channel before setting delegate=newChannel.

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[vikinghawk]

test to recreate the issue: https://gist.github.com/vikinghawk/54e1d80dcefa014c3ba60308c2486a26

[michaelklishin]

Thank you. The latter is likely the root cause here but I have no problem with the former. @acogoluegnes WDYT?

[acogoluegnes]

LGTM, will merge it in 4.4.x-stable once 4.4.2 is released.

[michaelklishin]

@vikinghawk thanks again for your excellent contributions!