Bump librt from 0.15.0 to 0.16.0

Bumps [librt](https://github.com/mypyc/librt) from 0.15.0 to 0.16.0.
- [Commits](mypyc/librt@v0.15.0...v0.16.0)

---
updated-dependencies:
- dependency-name: librt
  dependency-version: 0.16.0
  dependency-type: indirect
  update-type: version-update:semver-minor
...

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

Author: dependabot[bot]