Copy drupal-9.3.0.bare.standard.php.gz and drupal-9.3.0.filled.standard.php.gz from the Drupal 10 branch

Problem/Motivation

Follow-up from #3261486: Remove core updates added prior to 9.3.0 and adjust test coverage.

Does it make sense to add drupal-9.3.0.bare.standard.php.gz and drupal-9.3.0.filled.standard.php.gz to Drupal 9.3 and 9.4?

contrib modules with update tests that try to add Drupal 10 support can reference those files, instead of adding a check if the current Drupal version is Drupal 10, use drupal-9.3.0.bare.standard.php.gz. Else, use drupal-9.0.0.bare.standard.php.gz

Proposed resolution

Copy drupal-9.3.0.bare.standard.php.gz and drupal-9.3.0.filled.standard.php.gz from the Drupal 10 branch to Drupal 9.4 so contrib modules can use those dumps for their update tests in both Drupal versions.

Remaining tasks

User interface changes

API changes

Data model changes

Release notes snippet