$ git clone -n https://github.com/xcp-ng-rpms/xapi /var/lib/mock/v8.3-u-psafont1-10276-28852/root/chroot_tmpdir/scmroot/xapi
Cloning into '/var/lib/mock/v8.3-u-psafont1-10276-28852/root/chroot_tmpdir/scmroot/xapi'...
$ git fetch origin 0cadba2d62001ff609d4b49a56a0ed7bedacad00:KOJI_FETCH_HEAD
From https://github.com/xcp-ng-rpms/xapi
 * [new ref]         0cadba2d62001ff609d4b49a56a0ed7bedacad00 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 0cadba2 bump release for test build