Bump clap from 4.5.20 to 4.5.21 in /autorust (#522)

Bumps [clap](https://github.com/clap-rs/clap) from 4.5.20 to 4.5.21.
- [Release notes](https://github.com/clap-rs/clap/releases)
- [Changelog](https://github.com/clap-rs/clap/blob/master/CHANGELOG.md)
- [Commits](clap-rs/clap@clap_complete-v4.5.20...clap_complete-v4.5.21)

---
updated-dependencies:
- dependency-name: clap
  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>