AMQP1.0 client: Support HTTP/2 Websocket (backport #14616)

[mergify]

Proposed Changes

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If it fixes a bug or resolves a feature request, be sure to link to that issue.

A pull request that doesn't explain why the change was made has a much lower chance of being accepted.

Types of Changes

What types of changes does your code introduce to this project?
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• Bug fix (non-breaking change which fixes issue #NNNN)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause an observable behavior change in existing systems)
• Documentation improvements (corrections, new content, etc)
• Cosmetic change (whitespace, formatting, etc)
• Build system and/or CI

Checklist

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You can also fill these out after creating the PR.
This is simply a reminder of what we are going to look for before merging your code.

• Mandatory: I (or my employer/client) have have signed the CA (see https://github.com/rabbitmq/cla)
• I have read the CONTRIBUTING.md document
• I have added tests that prove my fix is effective or that my feature works
• All tests pass locally with my changes
• If relevant, I have added necessary documentation to https://github.com/rabbitmq/rabbitmq-website
• If relevant, I have added this change to the first version(s) in release-notes that I expect to introduce it

Further Comments

If this is a relatively large or complex change, kick off the discussion by explaining why you chose the solution
you did and what alternatives you considered, etc.

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This is an automatic backport of pull request #14616 done by [Mergify](https://mergify.com).