$ git clone -n https://src.fedoraproject.org/rpms/mailman3.git /var/lib/mock/f45-build-17950-506/root/chroot_tmpdir/scmroot/mailman3
Cloning into '/var/lib/mock/f45-build-17950-506/root/chroot_tmpdir/scmroot/mailman3'...
$ git fetch origin fe9073e414322a0120a2961a3f0a21dc9d030171:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/mailman3
 * [new ref]         fe9073e414322a0120a2961a3f0a21dc9d030171 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at fe9073e Rebuilt for https://fedoraproject.org/wiki/Fedora_45_Mass_Rebuild