$ git clone -n https://github.com/xcp-ng-rpms/xapi.git /var/lib/mock/v8.3-u-asultanov2-10832-29347/root/chroot_tmpdir/scmroot/xapi
Cloning into '/var/lib/mock/v8.3-u-asultanov2-10832-29347/root/chroot_tmpdir/scmroot/xapi'...
$ git fetch origin eff05391a2a52a982c7fdd4fce110fb7d1a4a8e8:KOJI_FETCH_HEAD
From https://github.com/xcp-ng-rpms/xapi
 * [new ref]         eff05391a2a52a982c7fdd4fce110fb7d1a4a8e8 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at eff0539 bump release for test build