PIMS-620 Frontend Testing Addition

[dbarkowsky]

🎯 Summary

PIMS-610

Changes

• Adds a testing framework to the new react-app component.

🔰 Checklist

• I have read and agree with the following checklist and am following the guidelines in our Code of Conduct document.

• 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 where required.
• I have tested my changes to the best of my ability.
• My changes generate no new warnings.

[dbarkowsky]

Some current issues:

1. Image imports seem to fail. I've tried mocking any svg or png types that are imported using the path mapping, but it doesn't seem to pick those up.
2. The .css imports seem to cause rendering issues as well.
3. For some reason, .inTheDocument() is not recognized for me.

[GrahamS-Quartech]

These tests should be good to go now. I don't have the image import issue but css imports are fixed now. .inTheDocument was being overwritten by importing describe, etc for jest it seems. Note that prettier v3 is unsupported for jest apparently, so I've just disabled it. Don't think this matters but figured I'd mention it.