Update clap requirement from 2.19 to 3.0
Update clap requirement from 2.19 to 3.0

Updates the requirements on [clap](https://github.com/clap-rs/clap) to permit the latest version.
- [Release notes](https://github.com/clap-rs/clap/releases)
- [Changelog](https://github.com/clap-rs/clap/blob/master/CHANGELOG.md)
- [Commits](https://github.com/clap-rs/clap/compare/clap_generate-v3.0.0-rc.0...clap_complete-v3.0.0)

---
updated-dependencies:
- dependency-name: clap
  dependency-type: direct:production
...

Signed-off-by: dependabot[bot] <5bdcd3c0d4d24ae3e71b3b452a024c6324c7e4bb@github.com>
TomasTomecek/pretty-git-prompt,TomasTomecek/pretty-git-prompt,TomasTomecek/pretty-git-prompt