build(deps): bump actions/setup-python from 5 to 6
Bumps [actions/setup-python](https://github.com/actions/setup-python)
from 5 to 6.
- [Release notes](https://github.com/actions/setup-python/releases)
- [Commits](https://github.com/actions/setup-python/compare/v5...v6)
Signed-off-by: Junio C Hamano <gitster@pobox.com>
authored by