[azeventhubs] Add in fault injector integration, similar to amqpproxy (#41284)

* Adding in a fault injector test - pretty basic, but we can expand it to take advantage of the other fault injectors.

* Remove other cases, they aren't used yet.

* Removing debug logging

* Use pascal casing, which is better than underscores and complies with all standards.

* Fixing incorrect function usage

* Update name

* Renaming according to copilot's suggestion

* Updating based on feedback:
- copilot flagged our worker thread that we didn't join. Used Kashif's syntax for timeout, and removed sleep.
- Fixing some warnings (accessing a private variable, and an unused parameter.

* Formatted using the vscode black formatter.

* - Remove unused imports
- Remove unused args, suggested by @swathipil

* Resolving some more comments - mostly just removing some dead comments.
Also, adding in sslcontext to remove some boilerplate from the test.

* Switching to a design that @swathipil suggested:
- Have a single fixture function, and use parametrize to pass in values at the test level
- Pass back a general client_args dict+values instead of specifying each value when creating the client

* More code to trim!

Also...the formatter got at the file again.

* Working around a lack of pytest knowledge on my part - just returning the client_args as part of the yield from the fixture.

Everything else works though, so that's just one last thing.

* Comment out the debug lines.

* Remove comment, the yield is fine.

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Co-authored-by: ripark <[email protected]>

Author: richardpark-msft

sdk/eventhub/azure-eventhub/tests/.gitignore

@@ -4,4 +4,7 @@
 
 # ignoring the key files so they don't get checked in.
 *-bin-*.txt
-*-tlskeys.txt
+*-tlskeys.txt
+server.crt
+server.key
+faultinjector-traffic.json