Merge pull request #2442 from tisnik/lcore-3581-ruf-rule-fixes

LCORE-3581: RUF rule fixes

Author: tisnik

src/app/endpoints/vector_stores.py

@@ -539,7 +539,7 @@ async def create_file(  # pylint: disable=too-many-branches,too-many-statements
             response = FileTooLargeResponse.from_backend_rejection(message=str(e))
         else:
             response = InternalServerErrorResponse.query_failed(
-                cause=f"File upload rejected by Llama Stack: {str(e)}"
+                cause=f"File upload rejected by Llama Stack: {e!s}"
             )
             # Override to use 400 status code since it's a client error
             response.status_code = status.HTTP_400_BAD_REQUEST

tests/unit/app/test_routers.py

@@ -114,7 +114,7 @@ def get_router_prefix(self, router: Any) -> Optional[str]:
         ------
             IndexError: If the router is not registered in the mock app.
         """
-        return list(filter(lambda r: r[0] == router, self.routers))[0][1]
+        return next(filter(lambda r: r[0] == router, self.routers))[1]
 
 
 def test_include_routers() -> None: