$ git clone -n https://src.fedoraproject.org/rpms/rsnapshot.git /var/lib/mock/f45-build-34686-690/root/chroot_tmpdir/scmroot/rsnapshot
Cloning into '/var/lib/mock/f45-build-34686-690/root/chroot_tmpdir/scmroot/rsnapshot'...
$ git fetch origin 646dc6ca7010d97d5ae3380601df174f3bb89775:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rsnapshot
 * [new ref]         646dc6ca7010d97d5ae3380601df174f3bb89775 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 646dc6c Rebuilt for https://fedoraproject.org/wiki/Fedora_45_Mass_Rebuild