$ git clone -n https://github.com/xcp-ng-rpms/xapi.git /var/lib/mock/v8.3-u-abourgeois1-10186-28772/root/chroot_tmpdir/scmroot/xapi
Cloning into '/var/lib/mock/v8.3-u-abourgeois1-10186-28772/root/chroot_tmpdir/scmroot/xapi'...
$ git fetch origin 84261bee9b3816eb9dcad87f188f3d3ab5fda3a1:KOJI_FETCH_HEAD
From https://github.com/xcp-ng-rpms/xapi
 * [new ref]         84261bee9b3816eb9dcad87f188f3d3ab5fda3a1 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 84261be bump release for test build