$ git clone -n https://github.com/xcp-ng-rpms/xapi.git /var/lib/mock/v8.3-u-asultanov2-9855-28570/root/chroot_tmpdir/scmroot/xapi
Cloning into '/var/lib/mock/v8.3-u-asultanov2-9855-28570/root/chroot_tmpdir/scmroot/xapi'...
$ git fetch origin bf24f67401e8f24206dc005baaf5b69916a995f6:KOJI_FETCH_HEAD
From https://github.com/xcp-ng-rpms/xapi
 * [new ref]         bf24f67401e8f24206dc005baaf5b69916a995f6 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at bf24f67 bump release for test build