Migrated AMQP.RabbitMQ Tests to TestContainers

[Aaronontheweb]

Changes

The Docker.NET code in this project was extremely byte-rotted, so migrated everything to use TestContainers.RabbitMQ.

Worth noting: it looks like none of these tests have been run properly on the build server for some time. Still looking into that, but in the meantime I'm executing these locally.

Checklist

For significant changes, please ensure that the following have been completed (delete if not relevant):

• [x] This change follows the Akka.NET API Compatibility Guidelines.
• [x] This change follows the Akka.NET Wire Compatibility Guidelines.
• [x] I have reviewed my own pull request.

[Aaronontheweb]

There's 4 legitimate failing unit tests here - will need to look at that.

[Aaronontheweb]

Ok, have tests running on all platforms again - that's an improvement