Build: Bump mmh3 from 5.2.0 to 5.2.1

Bumps [mmh3](https://github.com/hajimes/mmh3) from 5.2.0 to 5.2.1.
- [Release notes](https://github.com/hajimes/mmh3/releases)
- [Changelog](https://github.com/hajimes/mmh3/blob/master/CHANGELOG.md)
- [Commits](hajimes/mmh3@v5.2.0...v5.2.1)

---
updated-dependencies:
- dependency-name: mmh3
  dependency-version: 5.2.1
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

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Author: dependabot[bot]