Update dependency minitest to v5.20.0

[renovate[bot]]

This PR contains the following updates:

Package	Change	Age	Adoption	Passing	Confidence
minitest	'5.19.0' -> '5.20.0'

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Release Notes

minitest/minitest (minitest)

### [`v5.20.0`](https://togithub.com/minitest/minitest/compare/v5.19.0...v5.20.0) [Compare Source](https://togithub.com/minitest/minitest/compare/v5.19.0...v5.20.0)

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Configuration

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