Make Playwright tests async

[radium-v]

Pull Request

📖 Description

This PR rewrites all Playwright tests in fast-foundation to be async/parallel.

👩‍💻 Reviewer Notes

The tests may be slower in this mode, which is why they were initially written to be synchronous. However, the synchronous approach has caused issues regarding cleanup between individual tests, as well as flakiness. The async approach is the recommended way to write Playwright tests.

📑 Test Plan

All tests in fast-foundation should pass as expected.

✅ Checklist

General

• [x] I have included a change request file using $ yarn change
• [x] I have added tests for my changes.
• [x] I have tested my changes.
• [ ] I have updated the project documentation to reflect my changes.
• [x] I have read the CONTRIBUTING documentation and followed the standards for this project.

⏭ Next Steps

The next step is to migrate all tests to use a standalone harness instead of Storybook. This will improve the performance of each test by reducing page load duration, and will allow us to more comfortably upgrade Storybook for local development.

[janechu]

Due to the number of conflicts and our work to close out #6951, we will be closing this PR as it is more of a nice-to-have.