$ git clone -n https://src.fedoraproject.org/rpms/rubygem-colorize.git /var/lib/mock/f45-build-34873-692/root/chroot_tmpdir/scmroot/rubygem-colorize
Cloning into '/var/lib/mock/f45-build-34873-692/root/chroot_tmpdir/scmroot/rubygem-colorize'...
$ git fetch origin 6025a5a7ade5f9f01c93653895af831b87501038:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rubygem-colorize
 * [new ref]         6025a5a7ade5f9f01c93653895af831b87501038 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 6025a5a Rebuilt for https://fedoraproject.org/wiki/Fedora_45_Mass_Rebuild