$ git clone -n https://src.fedoraproject.org/rpms/rubygem-redcarpet.git /var/lib/mock/f45-build-35212-694/root/chroot_tmpdir/scmroot/rubygem-redcarpet
Cloning into '/var/lib/mock/f45-build-35212-694/root/chroot_tmpdir/scmroot/rubygem-redcarpet'...
$ git fetch origin d3a04cd22876c11498e211a0802740a0982e8722:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rubygem-redcarpet
 * [new ref]         d3a04cd22876c11498e211a0802740a0982e8722 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at d3a04cd Rebuilt for https://fedoraproject.org/wiki/Fedora_45_Mass_Rebuild