Bump prettyplease from 0.2.9 to 0.2.12 (#3365)

Bumps [prettyplease](https://github.com/dtolnay/prettyplease) from 0.2.9 to 0.2.12.
- [Release notes](https://github.com/dtolnay/prettyplease/releases)
- [Commits](dtolnay/prettyplease@0.2.9...0.2.12)

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

Signed-off-by: dependabot[bot] <[email protected]>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>