fix(backend): Fix Black formatting for _extract_current_user signature

Keep function signature on single line as per Black's preference for
signatures under 100 characters.

Author: remyluslosius

backend/app/middleware/authorization_middleware.py

@@ -302,9 +302,7 @@ def _match_pattern(self, request_path: str, pattern: str) -> bool:
 
         return True
 
-    async def _extract_current_user(
-        self, request: Request
-    ) -> Optional[Dict[str, Any]]:
+    async def _extract_current_user(self, request: Request) -> Optional[Dict[str, Any]]:
         """
         Extract current user from request authentication
         """