Fix hanging process when reassigning UID to OpenStack cloud service providers.

Problem/Motivation

This issue was found during BDD testing.

When deleting a user, and there are OpenStack cloud service providers assigned to that UID, the following update code runs during the deletion process.

function openstack_cloud_config_update(CloudConfig $cloud_config): void {
  if ($cloud_config->bundle() === 'openstack') {
    openstack_update_resources($cloud_config);
  }
}

In doing so, it will try to update all openstack instances. This causes the system to hang, and never return. Ultimately, it hogs up all DB resources.

The problem arises because Drupal's user delete runs in batch mode, utilizing the progress bar, known as Progressive batch. If openstack_update_resources($cloud_config); runs, it will try to run another batch process to update resources. That batch runs in non-progressive mode.

Doing so confuses the original batch processing. (We have both progressive and non-progressive batch processing happening) Drupal will pick up CloudService::batchProcessEntities() indefinitely, and never return.

tl;dr: You can't run a progressive batch and within that batch try to run a non-progressive batch. It confuses Drupal and causes it to loop and never return.