Update dependency mypy to v0.971

[renovate[bot]]

This PR contains the following updates:

Package	Change	Age	Adoption	Passing	Confidence
mypy (source, changelog)	==0.961 -> ==0.971

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Release Notes

python/mypy

### [`v0.971`](https://togithub.com/python/mypy/compare/v0.961...v0.971) [Compare Source](https://togithub.com/python/mypy/compare/v0.961...v0.971)

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