$ git clone -n https://src.fedoraproject.org/rpms/plasma-mobile.git /var/lib/mock/f42-build-862465-170829/root/chroot_tmpdir/scmroot/plasma-mobile
Cloning into '/var/lib/mock/f42-build-862465-170829/root/chroot_tmpdir/scmroot/plasma-mobile'...
$ git fetch origin f09b94c714a4aa467b91dd28d5c3781f196ffcf3:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/plasma-mobile
 * [new ref]         f09b94c714a4aa467b91dd28d5c3781f196ffcf3 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at f09b94c 6.2.4