Stop the machines complaining

Author: tpoliaw

src/blueapi/service/main.py

@@ -181,8 +181,9 @@ def inner(request: Request, access_token: Annotated[str, Depends(bearer_token)])
 async def opa(
     request: Request, token: Annotated[str, Depends(bearer_token)]
 ) -> OpaUserClient | None:
-    if client := cast(OpaClient | None, getattr(request.app.state, "authz", None)):
+    if client := cast(OpaClient, getattr(request.app.state, "authz", None)):
         return client.for_token(token)
+    return None
 
 async def submit_permission(
     task_request: Annotated[TaskRequest, Body()],