$ git clone -n https://github.com/xcp-ng-rpms/xapi.git /var/lib/mock/v8.3-u-gtn1-10262-28835/root/chroot_tmpdir/scmroot/xapi
Cloning into '/var/lib/mock/v8.3-u-gtn1-10262-28835/root/chroot_tmpdir/scmroot/xapi'...
$ git fetch origin 689603ef3a08880530cb9ae7d5ef3b36f0933556:KOJI_FETCH_HEAD
From https://github.com/xcp-ng-rpms/xapi
 * [new ref]         689603ef3a08880530cb9ae7d5ef3b36f0933556 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 689603e bump release for test build