$ git clone -n https://src.fedoraproject.org/rpms/golang-github-jhillyerd-enmime.git /var/lib/mock/f40-build-2582720-62396/root/chroot_tmpdir/scmroot/golang-github-jhillyerd-enmime
Cloning into '/var/lib/mock/f40-build-2582720-62396/root/chroot_tmpdir/scmroot/golang-github-jhillyerd-enmime'...
$ git fetch origin dcd98a183bc9afe9233e1ac6e67132aacac3662f:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/golang-github-jhillyerd-enmime
 * [new ref]         dcd98a183bc9afe9233e1ac6e67132aacac3662f -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at dcd98a1 Update to 1.2.0 - Closes rhbz#2225859 rhbz#2171519