$ git clone -n https://src.fedoraproject.org/rpms/perl-UNIVERSAL-ref.git /var/lib/mock/f45-build-27291-622/root/chroot_tmpdir/scmroot/perl-UNIVERSAL-ref
Cloning into '/var/lib/mock/f45-build-27291-622/root/chroot_tmpdir/scmroot/perl-UNIVERSAL-ref'...
$ git fetch origin 4482fff64822d40dfb33f932b34e8def7b7cb03d:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/perl-UNIVERSAL-ref
 * [new ref]         4482fff64822d40dfb33f932b34e8def7b7cb03d -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 4482fff Perl 5.44 rebuild