$ git clone -n https://src.fedoraproject.org/rpms/perl-Algorithm-Cron.git /var/lib/mock/f45-build-21574-586/root/chroot_tmpdir/scmroot/perl-Algorithm-Cron
Cloning into '/var/lib/mock/f45-build-21574-586/root/chroot_tmpdir/scmroot/perl-Algorithm-Cron'...
$ git fetch origin 6c490db1f81eb39930f25803f0f75bdbc0b8cbab:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/perl-Algorithm-Cron
 * [new ref]         6c490db1f81eb39930f25803f0f75bdbc0b8cbab -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 6c490db Rebuilt for https://fedoraproject.org/wiki/Fedora_45_Mass_Rebuild