$ git clone -n https://github.com/xcp-ng-rpms/xapi.git /var/lib/mock/v8.3-u-psafont2-9759-28474/root/chroot_tmpdir/scmroot/xapi
Cloning into '/var/lib/mock/v8.3-u-psafont2-9759-28474/root/chroot_tmpdir/scmroot/xapi'...
$ git fetch origin c16a0ffce8377a826b8e6a3668a27d420141cbc9:KOJI_FETCH_HEAD
From https://github.com/xcp-ng-rpms/xapi
 * [new ref]         c16a0ffce8377a826b8e6a3668a27d420141cbc9 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at c16a0ff bump release for test build