Add Jest Framework to Frontend

[WillCWX]

Pull Request

Description

• Adds Jest framework to test the frontend

• yarn test for jest suite

• yarn test:update to update snapshots for large UI changes

• yarn coverage to generate a coverage report

• We will go with the structure of src/{folder}/__tests__ for each folder to keep the tests close to their components

  • src/{folder}/{sub_folder}/__tests__ for sub folders that are large

• Snapshot tests of current pages added

  • Assignment page is stuck on a loading snapshot as I can't await the Promise

• Github actions added to run test suite and generate coverage report (report not yet placed as a badge%)

• Deletes some unneeded imports for user page (sry the lint keeps nagging)

Dependencies added to dev:

• Jest, its typescript modules and environments
• testing-library/react and testing-library/jest-dom
• ts-node

Related Issue(s)
#27 , may close after some tests written for components, helpers and utilities

Additional Notes/References

You may need to run yarn upgrade as there are issues with yarn and jest according to this.
I solved this issue in the github actions by adding the fix:
"resolutions": { "wrap-ansi": "7.0.0", "string-width": "4.1.0" }

but any side effects from this is unknown

I'll write a quick cheat sheet for jest on frontend later

There is a console log in dateUtils.ts that is caught in this test lol

[tryyang2001]

LGTM, great work. The test code is clear and readable :DD