prevent file records cascade deletion

src/Service/Cron/Job/CleanWorkToDo.php

@@ -103,7 +103,7 @@ class CleanWorkToDo extends BaseCronJob
 
                 // Set DELETION_REQUESTED status for all associated files
                 $this->connection->executeStatement(
-                    "UPDATE File SET status = ? WHERE work_id = ?",
+                    "UPDATE File SET status = ?, work_id = null WHERE work_id = ?",
                     [FileStatusEnum::DELETION_REQUESTED->value, $workId]
                 );