Add unit tests

[rhoegg]

There appears to be a munit test set up in json-logger-test-suite.xml using test-mule-config.xml but I don't see it run in the default maven test lifecycle:

[INFO] --- surefire:3.2.5:test (default-test) @ json-logger ---
[INFO] ------------------------------------------------------------------------
[INFO] BUILD SUCCESS
[INFO] ------------------------------------------------------------------------
[INFO] Total time:  4.621 s
[INFO] Finished at: 2025-09-01T17:10:46-05:00
[INFO] ------------------------------------------------------------------------

This issue tracks the creation of a baseline unit test suite that covers all the core functionality of this connector. If we want to make multiple issues, we should link them here.

[mtransier]

There is a GitHub action running the MUnit tests for pull requests. The MUnits are triggered by mvn verify. This is due to the munit-extensions-maven-plugin, which by default assumes JUnit tests (and yes, there are no JUnits). Not sure if it is possible to bind the MUnit execution to the test phase, I had tried that in the past to no avail.

[rhoegg]

This is good, I wanted to get an issue on the board for the creation of the tests themselves that cover the functionality of the connector