fix: clean up more unneeded cast

Author: georgeh0

python/cocoindex/flow.py

@@ -955,7 +955,7 @@ def __call__(self, *args: Any, **kwargs: Any) -> DataSlice[T]:
     def _flow_info(self) -> TransformFlowInfo:
         if self._lazy_flow_info is not None:
             return self._lazy_flow_info
-        return cast(TransformFlowInfo, execution_context.run(self._flow_info_async()))
+        return execution_context.run(self._flow_info_async())
 
     async def _flow_info_async(self) -> TransformFlowInfo:
         if self._lazy_flow_info is not None: