$ git clone -n https://github.com/xcp-ng-rpms/unbound.git /var/lib/mock/v8.3-incoming-11548-29862/root/chroot_tmpdir/scmroot/unbound
Cloning into '/var/lib/mock/v8.3-incoming-11548-29862/root/chroot_tmpdir/scmroot/unbound'...
$ git fetch origin 7dd1fdf0048dc76b021afe372bb92aa5cdf8f85d:KOJI_FETCH_HEAD
From https://github.com/xcp-ng-rpms/unbound
 * [new ref]         7dd1fdf0048dc76b021afe372bb92aa5cdf8f85d -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 7dd1fdf BuildRequieres openssl-compat10-devel