ci: Add PHP error display for debugging in Drupal workflows

ci: Add PHP error display for debugging in Drupal workflows This commit enhances the Drupal testing workflows by enabling PHP error display and setting the error reporting level to `E_ALL`. This change will make it easier to debug issues encountered during the test runs. Additionally, it refactors the `Install Drupal site` step to correctly determine the web server user for `chown` operations, ensuring proper file ownership.