$ git clone -n https://github.com/xcp-ng-rpms/xcp-ng-release.git /var/lib/mock/v8.3-incoming-10202-28716/root/chroot_tmpdir/scmroot/xcp-ng-release
Cloning into '/var/lib/mock/v8.3-incoming-10202-28716/root/chroot_tmpdir/scmroot/xcp-ng-release'...
$ git fetch origin ea1e7c3fe142884b8344feab56dbc448f0316756:KOJI_FETCH_HEAD
From https://github.com/xcp-ng-rpms/xcp-ng-release
 * [new ref]         ea1e7c3fe142884b8344feab56dbc448f0316756 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at ea1e7c3 Preserve /etc/rsyslog.d/xenstore.conf if present