$ git clone -n https://src.fedoraproject.org/rpms/perl-Test-Differences.git /var/lib/mock/f45-build-26622-618/root/chroot_tmpdir/scmroot/perl-Test-Differences
Cloning into '/var/lib/mock/f45-build-26622-618/root/chroot_tmpdir/scmroot/perl-Test-Differences'...
$ git fetch origin fc7539b9b7256d02df8ae994494d9fc3217ac102:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/perl-Test-Differences
 * [new ref]         fc7539b9b7256d02df8ae994494d9fc3217ac102 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at fc7539b Rebuilt for https://fedoraproject.org/wiki/Fedora_45_Mass_Rebuild