Make pre-commit use clang-format from cvmfs
With the upgrade to Python 3.12 of LbEnv, the pre-commit hook for clang-format 8 does not work anymore.
The proper fix would be to upgrade the version of clang-format, but that requires a global reformatting for which we are not ready, so, for the time being, we use the same clang-format binary lb-format was using.