Introduce Prettier

[muodov]

Reviewer: @sammacbeth

Description:

https://app.asana.com/0/1201807839809179/1208561434802767/f
This PR:

• Introduces Prettier
• applies it to the whole codebase
  Recommend to review commit-by-commit because most of the diff is formatting auto-fix

Steps to test this PR:

Automated tests:

• Unit tests
• Integration tests

Reviewer Checklist:

• Ensure the PR solves the problem
• Review every line of code
• Ensure the PR does no harm by testing the changes thoroughly
• Get help if you're uncomfortable with any of the above!
• Determine if there are any quick wins that improve the implementation

PR Author Checklist:

• Get advice or leverage existing code
• Agree on technical approach with reviewer (if the changes are nuanced)
• Ensure that there is a testing strategy (and documented non-automated tests)
• Ensure there is a documented monitoring strategy (if necessary)
• Consider systems implications

[muodov]

@sammacbeth I'm assuming the codeQL warnings are safe to ignore because they apply to the test files, right?

[sammacbeth]

I haven't checked the full 16k lines of diff, so just assuming that prettier did everything correctly :/