$ git clone -n https://src.fedoraproject.org/rpms/perl-Test-Snapshot.git /var/lib/mock/f45-build-26848-619/root/chroot_tmpdir/scmroot/perl-Test-Snapshot
Cloning into '/var/lib/mock/f45-build-26848-619/root/chroot_tmpdir/scmroot/perl-Test-Snapshot'...
$ git fetch origin a0406ab79d971b5f05b10e1f57ba8a81d9ba5a55:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/perl-Test-Snapshot
 * [new ref]         a0406ab79d971b5f05b10e1f57ba8a81d9ba5a55 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at a0406ab Rebuilt for https://fedoraproject.org/wiki/Fedora_45_Mass_Rebuild