build: bump clap_mangen from 0.2.11 to 0.2.12

Bumps [clap_mangen](https://github.com/clap-rs/clap) from 0.2.11 to 0.2.12.
- [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_mangen-v0.2.11...clap_mangen-v0.2.12)

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

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

Author: dependabot[bot]

Cargo.lock

@@ -8,6 +8,6 @@ version = "0.7.0"
 
 [dependencies]
 clap = { version = "4.3.0", features = ["derive"] }
-clap_mangen = "0.2.11"
+clap_mangen = "0.2.12"
 itertools = "0.10.5"
 lib = { package = "git-branchless-lib", version = "0.7.0", path = "../git-branchless-lib" }