Bump parking_lot from 0.11.2 to 0.12.1

Bumps [parking_lot](https://github.com/Amanieu/parking_lot) from 0.11.2 to 0.12.1.
- [Release notes](https://github.com/Amanieu/parking_lot/releases)
- [Changelog](https://github.com/Amanieu/parking_lot/blob/master/CHANGELOG.md)
- [Commits](https://github.com/Amanieu/parking_lot/compare/0.11.2...0.12.1

)

---
updated-dependencies:
- dependency-name: parking_lot
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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