Add Pytest testing suite

[RafaelCenzano]

Add Pytest testing suite

Add pytest suite and test client creator. Also added a github actions workflow to autorun pytest to confirm tests are passing before approving pull requests.

Type of change

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• This change requires a documentation update

How Has This Been Tested?

Ran the flask app and new test suite.

Checklist:

• My code follows the style guidelines of this project
• I have performed a self-review of my code
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation
• My changes generate no new warnings
• I have added tests that prove my fix is effective or that my feature works (if a larger change)
• New and existing unit tests pass locally with my changes