$ git clone -n https://github.com/xcp-ng-rpms/xcp-ng-release.git /var/lib/mock/v8.3-incoming-10200-28716/root/chroot_tmpdir/scmroot/xcp-ng-release
Cloning into '/var/lib/mock/v8.3-incoming-10200-28716/root/chroot_tmpdir/scmroot/xcp-ng-release'...
$ git fetch origin a036eda3ccb2ce7c17d1e86ed0873b51e956808b:KOJI_FETCH_HEAD
From https://github.com/xcp-ng-rpms/xcp-ng-release
 * [new ref]         a036eda3ccb2ce7c17d1e86ed0873b51e956808b -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at a036eda Preserve /etc/rsyslog.d/xenstore.conf if present