Issue #3364958: Stages should be destroyed in the background, during cron runs

package_manager/src/Plugin/QueueWorker/Cleaner.php

@@ -49,9 +49,11 @@ final class Cleaner extends QueueWorkerBase implements ContainerFactoryPluginInt
   /**
    * {@inheritdoc}
    */
-  public function processItem(string $dir) {
+  public function processItem($dir) {
+    assert(is_string($dir));
+
     if (file_exists($dir)) {
-      $this->fileSystem->deleteRecursive($staging_root, function (string $path): void {
+      $this->fileSystem->deleteRecursive($dir, function (string $path): void {
         $this->fileSystem->chmod($path, 0777);
       });
     }