Bump flake8 from 5.0.4 to 6.0.0

Bumps [flake8](https://github.com/pycqa/flake8) from 5.0.4 to 6.0.0.
- [Release notes](https://github.com/pycqa/flake8/releases)
- [Commits](PyCQA/flake8@5.0.4...6.0.0)

---
updated-dependencies:
- dependency-name: flake8
  dependency-type: direct:development
  update-type: version-update:semver-major
...

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