$ git clone -n https://src.fedoraproject.org/rpms/kscreen.git /var/lib/mock/f40-build-803120-144180/root/chroot_tmpdir/scmroot/kscreen
Cloning into '/var/lib/mock/f40-build-803120-144180/root/chroot_tmpdir/scmroot/kscreen'...
$ git fetch origin e45c3ac959d97fccdf089b242a35da066dc1df20:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/kscreen
 * [new ref]         e45c3ac959d97fccdf089b242a35da066dc1df20 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at e45c3ac 6.0.3