Creation of dynamic property CRM_Temporarygroups_Upgrader::$queue is deprecated in PHP 8.3

Running \CRM_Temporarygroups_Upgrader_Base::enqueuePendingRevisions with PHP 8.3 you get the warning:

[PHP Deprecation] Creation of dynamic property CRM_Temporarygroups_Upgrader::$queue is deprecated at /var/www/html/httpdocs/sites/default/files/civicrm/ext/temporarygroups/CRM/Temporarygroups/Upgrader/Base.php:217

The declaration of the property queue is missing in the class \CRM_Temporarygroups_Upgrader_Base.