[ONNX] Refactor test_op_consistenct.py and test_fx_op_consistency.py (#100172)
## Summary
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### <samp>🤖 Generated by Copilot at 9255aa3</samp>
This pull request refactors the ONNX operator testing code to use a common module `./test/onnx/onnx_test_common.py` that defines constants, types, classes, and functions for testing ONNX operators. This improves the code quality, readability, and maintainability.
## Walkthrough
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### <samp>🤖 Generated by Copilot at 9255aa3</samp>
* Refactor the common code for testing ONNX operators from different files into `./test/onnx/onnx_test_common.py` ([link](https://github.com/pytorch/pytorch/pull/100172/files?diff=unified&w=0#diff-1b38383dc1a0228a835d83bb7c4ba2d0c1bcd41297be5c6336572c525846166eL10-R24), [link](https://github.com/pytorch/pytorch/pull/100172/files?diff=unified&w=0#diff-1b38383dc1a0228a835d83bb7c4ba2d0c1bcd41297be5c6336572c525846166eR33), [link](https://github.com/pytorch/pytorch/pull/100172/files?diff=unified&w=0#diff-1b38383dc1a0228a835d83bb7c4ba2d0c1bcd41297be5c6336572c525846166eR367-R623))
* Remove the unused and duplicated imports, constants, types, and classes for testing ONNX operators from `./test/onnx/test_fx_op_consistency.py` and `./test/onnx/test_op_consistency.py` ([link](https://github.com/pytorch/pytorch/pull/100172/files?diff=unified&w=0#diff-db2f78a51511bb172cbfde1b2f68272b8b33049abe2571cded27bcd0f3ae5fa4L28-R29), [link](https://github.com/pytorch/pytorch/pull/100172/files?diff=unified&w=0#diff-db2f78a51511bb172cbfde1b2f68272b8b33049abe2571cded27bcd0f3ae5fa4L43-R42), [link](https://github.com/pytorch/pytorch/pull/100172/files?diff=unified&w=0#diff-e968c9cb6fc6631cab526cb3a9fe66358c4c6e757e2a223a224b976471bcb753L28-R29), [link](https://github.com/pytorch/pytorch/pull/100172/files?diff=unified&w=0#diff-e968c9cb6fc6631cab526cb3a9fe66358c4c6e757e2a223a224b976471bcb753L43-R44))
* Import the `unittest`, `opinfo_core`, and `onnx_test_common` modules and the `fixme`, `skip`, and `xfail` functions in `./test/onnx/test_fx_op_consistency.py` and `./test/onnx/test_op_consistency.py` ( [link](https://github.com/pytorch/pytorch/pull/100172/files?diff=unified&w=0#diff-db2f78a51511bb172cbfde1b2f68272b8b33049abe2571cded27bcd0f3ae5fa4R36), [link](https://github.com/pytorch/pytorch/pull/100172/files?diff=unified&w=0#diff-e968c9cb6fc6631cab526cb3a9fe66358c4c6e757e2a223a224b976471bcb753L37-R37))
* Update the references to the constants, types, functions, and classes for testing ONNX operators in `./test/onnx/test_fx_op_consistency.py` and `./test/onnx/test_op_consistency.py` to use the definitions from `./test/onnx/onnx_test_common.py` ([link](https://github.com/pytorch/pytorch/pull/100172/files?diff=unified&w=0#diff-db2f78a51511bb172cbfde1b2f68272b8b33049abe2571cded27bcd0f3ae5fa4L324-R80), [link](https://github.com/pytorch/pytorch/pull/100172/files?diff=unified&w=0#diff-db2f78a51511bb172cbfde1b2f68272b8b33049abe2571cded27bcd0f3ae5fa4L389-R135), [link](https://github.com/pytorch/pytorch/pull/100172/files?diff=unified&w=0#diff-db2f78a51511bb172cbfde1b2f68272b8b33049abe2571cded27bcd0f3ae5fa4L405-R151), [link](https://github.com/pytorch/pytorch/pull/100172/files?diff=unified&w=0#diff-db2f78a51511bb172cbfde1b2f68272b8b33049abe2571cded27bcd0f3ae5fa4L455-R204), [link](https://github.com/pytorch/pytorch/pull/100172/files?diff=unified&w=0#diff-e968c9cb6fc6631cab526cb3a9fe66358c4c6e757e2a223a224b976471bcb753L333-R107), [link](https://github.com/pytorch/pytorch/pull/100172/files?diff=unified&w=0#diff-e968c9cb6fc6631cab526cb3a9fe66358c4c6e757e2a223a224b976471bcb753L434-R183), [link](https://github.com/pytorch/pytorch/pull/100172/files?diff=unified&w=0#diff-e968c9cb6fc6631cab526cb3a9fe66358c4c6e757e2a223a224b976471bcb753L448-R197), [link](https://github.com/pytorch/pytorch/pull/100172/files?diff=unified&w=0#diff-e968c9cb6fc6631cab526cb3a9fe66358c4c6e757e2a223a224b976471bcb753L494-R246))
Pull Request resolved: https://github.com/pytorch/pytorch/pull/100172
Approved by: https://github.com/justinchuby