Issue #3450318 by coffeemakr: Path traversal check is done twice

src/EventSubscriber/StageFileProxySubscriber.php

@@ -76,11 +76,6 @@ class StageFileProxySubscriber implements EventSubscriberInterface {
       return;
     }
 
-    // Disallow directory traversal.
-    if (in_array('..', explode('/', $request_path))) {
-      return;
-    }
-
     // Moving to parent directory is insane here, so prevent that.
     if (in_array('..', explode('/', $request_path))) {
       return;