Bump simplecov from 0.18.5 to 0.21.2
Bump simplecov from 0.18.5 to 0.21.2

Bumps [simplecov](https://github.com/simplecov-ruby/simplecov) from 0.18.5 to 0.21.2.
- [Release notes](https://github.com/simplecov-ruby/simplecov/releases)
- [Changelog](https://github.com/simplecov-ruby/simplecov/blob/main/CHANGELOG.md)
- [Commits](https://github.com/simplecov-ruby/simplecov/compare/v0.18.5...v0.21.2)

---
updated-dependencies:
- dependency-name: simplecov
  dependency-type: direct:development
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <5bdcd3c0d4d24ae3e71b3b452a024c6324c7e4bb@github.com>
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