fix(backend): disable type filter in attachment query

Comment out the type condition to allow retrieving all attachments
regardless of their type in the backend controller.

app/controller/backend/AttachmentController.php

@@ -58,7 +58,7 @@ class AttachmentController extends BaseController
             }
         }
         if($type){
-            $where[] = ['type', '=', $type];
+           // $where[] = ['type', '=', $type];
         }
         $name = input('name');
         if(!empty($name)){