style: ruff format

Author: azilbersteinSFDC

src/a2a/server/request_handlers/rest_handler.py

@@ -253,7 +253,9 @@ async def on_get_task(
             history_length = int(history_length_str) if history_length_str else None
         except ValueError:
             raise ServerError(
-                error=InvalidParamsError(message='historyLength must be a valid integer')
+                error=InvalidParamsError(
+                    message='historyLength must be a valid integer'
+                )
             ) from None
         params = GetTaskRequest(id=task_id, history_length=history_length)
         task = await self.request_handler.on_get_task(params, context)