$ git clone -n https://github.com/xcp-ng-rpms/xapi.git /var/lib/mock/v9.0-u-ydi1-11556-29863/root/chroot_tmpdir/scmroot/xapi
Cloning into '/var/lib/mock/v9.0-u-ydi1-11556-29863/root/chroot_tmpdir/scmroot/xapi'...
$ git fetch origin 89b1367b45aca0efa5f95eb8966d403cb256eb7d:KOJI_FETCH_HEAD
From https://github.com/xcp-ng-rpms/xapi
 * [new ref]         89b1367b45aca0efa5f95eb8966d403cb256eb7d -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 89b1367 bump release for test build