$ git clone -n https://src.fedoraproject.org/rpms/menu-cache.git /var/lib/mock/f41-build-846572-163108/root/chroot_tmpdir/scmroot/menu-cache
Cloning into '/var/lib/mock/f41-build-846572-163108/root/chroot_tmpdir/scmroot/menu-cache'...
$ git fetch origin 391a317573edddb70300f5c0606fddd0ec3f28e9:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/menu-cache
 * [new ref]         391a317573edddb70300f5c0606fddd0ec3f28e9 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 391a317 Update to the latest git