Bump minitest from 5.11.1 to 5.11.2
Bump minitest from 5.11.1 to 5.11.2

Bumps [minitest](https://github.com/seattlerb/minitest) from 5.11.1 to 5.11.2.
- [Changelog](https://github.com/seattlerb/minitest/blob/master/History.rdoc)
- [Commits](https://github.com/seattlerb/minitest/commits)
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