$ git clone -n https://src.fedoraproject.org/rpms/golang-github-aclements-moremath.git /var/lib/mock/f40-build-2245849-53791/root/chroot_tmpdir/scmroot/golang-github-aclements-moremath
Cloning into '/var/lib/mock/f40-build-2245849-53791/root/chroot_tmpdir/scmroot/golang-github-aclements-moremath'...
$ git fetch origin 08afd1664c21bee17165ff22e40b2b042ceb8281:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/golang-github-aclements-moremath
 * [new ref]         08afd1664c21bee17165ff22e40b2b042ceb8281 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 08afd16 Remove deprecated %patchN syntax