$ git clone -n https://github.com/xcp-ng-rpms/xapi.git /var/lib/mock/v8.3-u-pcoval2-10174-28761/root/chroot_tmpdir/scmroot/xapi
Cloning into '/var/lib/mock/v8.3-u-pcoval2-10174-28761/root/chroot_tmpdir/scmroot/xapi'...
$ git fetch origin 1243e281f5cec1e0ae9e788c92bf5b726783e716:KOJI_FETCH_HEAD
From https://github.com/xcp-ng-rpms/xapi
 * [new ref]         1243e281f5cec1e0ae9e788c92bf5b726783e716 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 1243e28 bump release for test build