Find a replacement for Karma

[hudson-newey]

Karma has been deprecated since April 2023.

The Angular has suggested Jest and Web Test Runner as replacements for Karma.

We should investigate which option will provide:

• The smoothest transition
  • Are the APIs and configs compatible with our existing code base?
• The most stable CI experience going forwards
• The fastest development experience
  • How intuitive is the testing framework
  • Can add threaded parallelism by using a new test runner (reducing the downtime waiting for tests to finish)