$ git clone -n https://src.fedoraproject.org/rpms/dtkwidget.git /var/lib/mock/f42-build-side-1-3568053-46743/root/chroot_tmpdir/scmroot/dtkwidget
Cloning into '/var/lib/mock/f42-build-side-1-3568053-46743/root/chroot_tmpdir/scmroot/dtkwidget'...
$ git fetch origin ff55edb6111bead5106c342db5b23fb983b60494:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/dtkwidget
 * [new ref]         ff55edb6111bead5106c342db5b23fb983b60494 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at ff55edb Rebuild (qt5)