Bump clarabel from 0.7.1 to 0.8.1

Bumps [clarabel](https://github.com/oxfordcontrol/Clarabel.rs) from 0.7.1 to 0.8.1.
- [Release notes](https://github.com/oxfordcontrol/Clarabel.rs/releases)
- [Changelog](https://github.com/oxfordcontrol/Clarabel.rs/blob/main/CHANGELOG.md)
- [Commits](oxfordcontrol/Clarabel.rs@v0.7.1...v0.8.1)

---
updated-dependencies:
- dependency-name: clarabel
  dependency-type: direct:development
  update-type: version-update:semver-minor
...

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