build(deps): update onnx requirement from <1.21.0,>1.12.0 to >1.12.0,<1.22.0 in /requirements (#21647)

build(deps): update onnx requirement in /requirements

Updates the requirements on [onnx](https://github.com/onnx/onnx) to permit the latest version.
- [Release notes](https://github.com/onnx/onnx/releases)
- [Changelog](https://github.com/onnx/onnx/blob/main/docs/Changelog-ml.md)
- [Commits](https://github.com/onnx/onnx/compare/v1.13.0...v1.21.0)

---
updated-dependencies:
- dependency-name: onnx
  dependency-version: 1.21.0
  dependency-type: direct:production
...

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