Make the repository initiate with Drupal 11 (as default)

[joshsedl]

The default should be Drupal 11, we might need to drop both Drupal 10 and Drupal 9 support, because of Drupal 11 using PHPUnit 10.x.

Furthermore, we need to

• Migrate the phpunit.xml to make it ready for PHPUnit 10.x.
• Adjust our "docker-compose.chromedriver.yaml", to be compatible with PHPUnit 10.x.
  • There is probably an existing ddev chromedriver plugin (just like phpmyadmin).

[joshsedl]

https://github.com/ddev/ddev-selenium-standalone-chrome works great instead of our custom chromedriver yml 👍

[joshsedl]

Seems that HTML Output is not default for PHPUnit 10.x, so we need to re-enable that somehow as well.

Found a way to fix it! https://drupal.stackexchange.com/questions/318185/phpunit-9-6-16-with-drupal-10-2-unable-to-write-to-output-directory-how-to-fix