pytorch

51bca2ca - [caffe2] fix -Wrange-loop-construct in onnx_exporter.cc (#56759)

[caffe2] fix -Wrange-loop-construct in onnx_exporter.cc (#56759) Summary: Pull Request resolved: https://github.com/pytorch/pytorch/pull/56759 ``` caffe2/caffe2/onnx/onnx_exporter.cc:415:21: error: loop variable 'it' creates a copy from type 'const std::pair<const std::basic_string<char>, int>' [-Werror,-Wrange-loop-construct] for (const auto it : blob_versions) { ^ caffe2/caffe2/onnx/onnx_exporter.cc:415:10: note: use reference type 'const std::pair<const std::basic_string<char>, int> &' to prevent copying for (const auto it : blob_versions) { ^~~~~~~~~~~~~~~ & ``` Reviewed By: yfeldblum Differential Revision: D27960126 fbshipit-source-id: fd46f37cf1aca9441209de8eb06add204046db95