Figure out if content_access.admin.inc needs to be upgraded

This code snippet appears around line 590 in content_access.module:

  // Delete possible acl settings.
  if (\Drupal::moduleHandler()->moduleExists('acl')) {
    \Drupal::modulehandler()->loadInclude('content_access', 'inc', 'content_access.admin');
    foreach (['view', 'update', 'delete'] as $op) {
      $acl_id = content_access_get_acl_id($node, $op);
      acl_delete_acl($acl_id);
    }
  }

It is a holdover from Drupal 7. The module it tries to load (content_access.admin.inc) was part of the Drupal 7 branch, but does not exist in the Drupal 10 branch.

This code doesn't crash the module, but it is obviously not doing anything sensible.

We need to figure what this piece of was supposed to do, and how to upgrade it for Drupal 10.