Improve Playwright tests

[bosschaert]

Playwright test changes:

• Added new test that navigates between pages by changing the URL and edits them. One of the pages has a sheet the other has text (covers 3 of the 4 items on https://github.com/adobe/da-live/wiki/TODO-%E2%80%90-Playwright-tests )
• Support for running the tests against a locally running da-collab and da-admin (triggered by setting the env var GITHUB_HEAD_REF=local which now also selects these locally via query param)
• Updated the regionaledit test to run in its own unique directory to allow multi browser tests to run concurrently without tripping over each other

How Has This Been Tested?

These are tests...

Types of changes

• [X] Bug fix (non-breaking change which fixes an issue)
• [ ] New feature (non-breaking change which adds functionality)
• [ ] Breaking change (fix or feature that would cause existing functionality to change)

Checklist:

• [X] I have signed the Adobe Open Source CLA.
• [X] My code follows the code style of this project.
• [ ] My change requires a change to the documentation.
• [ ] I have updated the documentation accordingly.
• [X] I have read the CONTRIBUTING document.
• [X] I have added tests to cover my changes.
• [X] All new and existing tests passed.

[aem-code-sync[bot]]

Hello, I'm the AEM Code Sync Bot and I will run some actions to deploy your branch and validate page speed. In case there are problems, just click a checkbox below to rerun the respective action.

• [ ] Re-run PSI checks
• [ ] Re-sync branch

Commits

* [224e6b1](https://github.com/adobe/da-live/commit/224e6b1504812c39acab4a0f0fb6ed072ba21e55) :white_check_mark: (latest) * [a8fdbfc](https://github.com/adobe/da-live/commit/a8fdbfc671b4c3e9ca4d78f645ed1c036ad6e571) :white_check_mark: * [e292e45](https://github.com/adobe/da-live/commit/e292e45c673f9fdbcff26bab72348204dcaa0af8) :white_check_mark: * [a44c354](https://github.com/adobe/da-live/commit/a44c354ff74be5eec33e0739304ec1d73121673c) :white_check_mark: * [10abb65](https://github.com/adobe/da-live/commit/10abb65336baaf784aa855fb124c2b2269fd3233) :white_check_mark: * [befb2fa](https://github.com/adobe/da-live/commit/befb2facfa7075ce9ea7d2940bdf02110e6b4c65) :white_check_mark: