$ git clone -n https://src.fedoraproject.org/rpms/kwin-x11.git /var/lib/mock/f42-build-side-1-3569443-46747/root/chroot_tmpdir/scmroot/kwin-x11
Cloning into '/var/lib/mock/f42-build-side-1-3569443-46747/root/chroot_tmpdir/scmroot/kwin-x11'...
$ git fetch origin 59064f02405adddc72d56e27d119be56180f4d07:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/kwin-x11
 * [new ref]         59064f02405adddc72d56e27d119be56180f4d07 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 59064f0 Update to 6.4.0.