Write initial unit tests

[surajkumar]

As a developer I want to...

be able to write unit tests for the code I write

So that...

we have confidence in the system we are developing

Context

We need some unit tests to test the functionality of our code. This issue does not cover integration tests.

Acceptance Criteria

GIVEN a new change is made to the codebase
THEN unit tests can be written
AND they should be run within a pre-merge Github Action