Update dependency minitest to v5.21.1

[renovate[bot]]

This PR contains the following updates:

Package	Change	Age	Adoption	Passing	Confidence
minitest (changelog)	'5.20.0' -> '5.21.1'

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Release Notes

minitest/minitest (minitest)

### [`v5.21.1`](https://togithub.com/minitest/minitest/compare/v5.21.0...v5.21.1) [Compare Source](https://togithub.com/minitest/minitest/compare/v5.21.0...v5.21.1) ### [`v5.21.0`](https://togithub.com/minitest/minitest/compare/v5.20.0...v5.21.0) [Compare Source](https://togithub.com/minitest/minitest/compare/v5.20.0...v5.21.0)

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Configuration

📅 Schedule: Branch creation - At any time (no schedule defined), Automerge - At any time (no schedule defined).

🚦 Automerge: Disabled by config. Please merge this manually once you are satisfied.

♻ Rebasing: Whenever PR becomes conflicted, or you tick the rebase/retry checkbox.

🔕 Ignore: Close this PR and you won't be reminded about this update again.

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• [ ] If you want to rebase/retry this PR, check this box

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[yegor256]

@rultor please, try to merge, since 3 checks have passed

[yegor256]

@rultor merge

[rultor]

@rultor please, try to merge, since 3 checks have passed

@yegor256 OK, I'll try to merge now. You can check the progress of the merge here

[rultor]

@rultor please, try to merge, since 3 checks have passed

@yegor256 Done! FYI, the full log is here (took me 2min)

[rultor]

@rultor merge

@renovate[bot] @yegor256 The pull request is closed already, so I can't merge it

[rultor]

@rultor merge

@yegor256 I'm sorry, I don't understand you :( Check this page and try again please