Bump the rust-dependencies group across 1 directory with 2 updates

Bumps the rust-dependencies group with 2 updates in the / directory: [libherokubuildpack](https://github.com/heroku/libcnb.rs) and [ureq](https://github.com/algesten/ureq).


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)

Updates `ureq` from 2.10.1 to 2.12.1
- [Changelog](https://github.com/algesten/ureq/blob/main/CHANGELOG.md)
- [Commits](algesten/ureq@2.10.1...2.12.1)

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

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

Cargo.toml

@@ -25,7 +25,7 @@ indoc = "2"
 # libcnb has a much bigger impact on buildpack behaviour than any other dependencies,
 # so it's pinned to an exact version to isolate it from lockfile refreshes.
 libcnb = "=0.26.0"
-libherokubuildpack = { version = "=0.26.0", default-features = false, features = ["log"] }
+libherokubuildpack = { version = "=0.26.1", default-features = false, features = ["log"] }
 serde = "1"
 tar = { version = "0.4", default-features = false }
 ureq = { version = "2", default-features = false, features = ["tls"] }