Bump clang-format from 20.1.8 to 21.1.8
Bumps [clang-format](https://github.com/ssciwr/clang-format-wheel) from 20.1.8 to 21.1.8.
- [Release notes](https://github.com/ssciwr/clang-format-wheel/releases)
- [Commits](https://github.com/ssciwr/clang-format-wheel/compare/v20.1.8...v21.1.8)
---
updated-dependencies:
- dependency-name: clang-format
dependency-version: 21.1.8
dependency-type: direct:production
update-type: version-update:semver-major
...
Signed-off-by: dependabot[bot] <support@github.com>