Bump comrak from 0.38.0 to 0.39.0 in /autorust (#617)

Bumps [comrak](https://github.com/kivikakk/comrak) from 0.38.0 to 0.39.0.
- [Release notes](https://github.com/kivikakk/comrak/releases)
- [Changelog](https://github.com/kivikakk/comrak/blob/main/changelog.txt)
- [Commits](kivikakk/comrak@v0.38.0...v0.39.0)

---
updated-dependencies:
- dependency-name: comrak
  dependency-version: 0.39.0
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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

Author: dependabot[bot]

autorust/Cargo.lock

@@ -17,7 +17,7 @@ heck = "0.5"
 regex = "1"
 indexmap = { version = "2", features = ["serde"] }
 path_abs = "0.5"
-comrak = "0.38"
+comrak = "0.39"
 serde = "1"
 http-types = "2"
 once_cell = "1"