$ git clone -n https://src.fedoraproject.org/rpms/spamass-milter.git /var/lib/mock/f45-build-36266-702/root/chroot_tmpdir/scmroot/spamass-milter
Cloning into '/var/lib/mock/f45-build-36266-702/root/chroot_tmpdir/scmroot/spamass-milter'...
$ git fetch origin ac08687b19d4563244b650bb895c87cf28539fc4:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/spamass-milter
 * [new ref]         ac08687b19d4563244b650bb895c87cf28539fc4 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at ac08687 Rebuilt for https://fedoraproject.org/wiki/Fedora_45_Mass_Rebuild