Checklist for updating an existing operator

Maintainer @justinchuby

- [ ] Update the opset in `defs.cc`
- [ ] Move the old definition of `old.cc`
- [ ] Add the operator to `onnx/defs/operator_sets.h` or `onnx/defs/operator_sets_ml.h`
- [ ] Create node tests
- [ ] Disable the tests in `test_backend_onnxruntime.py`
- [ ] Create reference implementation
- [ ] Update version converter
- [ ] Create shape inference and checker tests
- [ ] Build docs or use the `auto update doc` label on the GitHub pull request to update the generated documentation

Reference

• https://github.com/onnx/onnx/pull/4862