Goal: 

• As a developer I want at least one unit tests for each kind of component.

Acceptance Criteria:

• One interactor unit test.
• One Repository unit test.
• One Presenter unit test.
• One Router unit test.
• todo: One Handler (one operation) unit test.
• One event handler unit test (kafka).
• One middleware unit test.
• todo: One application service test (check start, stop, and context finalization).
• Enhance developer unit test documentation with the above at 'docs/TESTING.mg'.