fix http NotFound call in pygrack

rhodecode/lib/middleware/pygrack.py

@@ -194,7 +194,7 b' class GitDirectory(object):'
                                     os.path.join(content_path, '.git'),
                                     self.username)
             else:
-                return exc.HTTPNotFound()(environ, start_response, self.username)
+                return exc.HTTPNotFound()(environ, start_response)
         return app(environ, start_response)