[Documentation] Version compatibility

[mkczyk]

Is your feature request related to a problem? Please describe.

README says that amqp-client can be used with 3.x server:

This client releases are independent of RabbitMQ server releases and can be used with RabbitMQ server 3.x.

But the latest version of server is 4.x (4.0.7).

Is the latest version of amqp-client compatible with the latest server? I guess it's obvious that it is, only the documentation is not updated. It's worth updating so it doesn't confuse.

Describe the solution you'd like

Update from 3.x to 3.x/4.x or 3.x or later.

Describe alternatives you've considered

No response

Additional context

No response

[michaelklishin]

@mkczyk you could have submitted a PR.