$ git clone -n https://src.fedoraproject.org/rpms/plasma-mobile.git /var/lib/mock/f42-build-side-1-3566303-46733/root/chroot_tmpdir/scmroot/plasma-mobile
Cloning into '/var/lib/mock/f42-build-side-1-3566303-46733/root/chroot_tmpdir/scmroot/plasma-mobile'...
$ git fetch origin 61fed13fac42dfc0eb30920f9635e638b6b973b6:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/plasma-mobile
 * [new ref]         61fed13fac42dfc0eb30920f9635e638b6b973b6 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 61fed13 6.4.0