fix lint

Author: ajac-zero

pydantic_ai_slim/pydantic_ai/providers/openrouter.py

@@ -86,7 +86,7 @@ def __init__(self, *, api_key: str, http_referer: str, x_title: str) -> None: ..
 
     @overload
     def __init__(self, *, api_key: str, http_referer: str, x_title: str, http_client: httpx.AsyncClient) -> None: ...
-      
+
     @overload
     def __init__(self, *, http_client: httpx.AsyncClient) -> None: ...