build(deps-dev): bump mutmut from 2.4.4 to 2.5.0

Bumps [mutmut](https://github.com/boxed/mutmut) from 2.4.4 to 2.5.0.
- [Changelog](https://github.com/boxed/mutmut/blob/master/HISTORY.rst)
- [Commits](boxed/mutmut@2.4.4...2.5.0)

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

Signed-off-by: dependabot[bot] <[email protected]>