Bump libherokubuildpack in the rust-dependencies group (#170)

Bumps the rust-dependencies group with 1 update: [libherokubuildpack](https://github.com/heroku/libcnb.rs).


Updates `libherokubuildpack` from 0.26.0 to 0.26.1
- [Release notes](https://github.com/heroku/libcnb.rs/releases)
- [Changelog](https://github.com/heroku/libcnb.rs/blob/main/CHANGELOG.md)
- [Commits](heroku/libcnb.rs@v0.26.0...v0.26.1)

---
updated-dependencies:
- dependency-name: libherokubuildpack
  dependency-type: direct:production
  update-type: version-update:semver-patch
  dependency-group: rust-dependencies
...

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