Bump up the ONNX default opset version to 10 (#17419)
Summary:
Align with the master of ONNX.
Pull Request resolved: https://github.com/pytorch/pytorch/pull/17419
Reviewed By: zrphercule
Differential Revision: D14197985
Pulled By: houseroad
fbshipit-source-id: 13fc1f7786aadbbf5fe83bddf488fee3dedf58ce
