Update dependency flake8 to v6

[renovate[bot]]

This PR contains the following updates:

Package	Change	Age	Adoption	Passing	Confidence
flake8 (changelog)	==5.0.4 -> ==6.0.0

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Release Notes

pycqa/flake8

### [`v6.0.0`](https://togithub.com/pycqa/flake8/compare/5.0.4...6.0.0) [Compare Source](https://togithub.com/pycqa/flake8/compare/5.0.4...6.0.0)

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Configuration

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