build(deps): bump jobserver from 0.1.27 to 0.1.28

Bumps [jobserver](https://github.com/alexcrichton/jobserver-rs) from 0.1.27 to 0.1.28.
- [Commits](https://github.com/alexcrichton/jobserver-rs/commits)

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

Signed-off-by: dependabot[bot] <support@github.com>