$ git clone -n https://src.fedoraproject.org/rpms/R-htmltools.git /var/lib/mock/f40-build-2257459-54320/root/chroot_tmpdir/scmroot/R-htmltools
Cloning into '/var/lib/mock/f40-build-2257459-54320/root/chroot_tmpdir/scmroot/R-htmltools'...
$ git fetch origin 6ab8d30f2fb089056e7476bbb0a80d9c2639b2f3:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/R-htmltools
 * [new ref]         6ab8d30f2fb089056e7476bbb0a80d9c2639b2f3 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 6ab8d30 0.5.7