$ git clone -n https://github.com/xcp-ng-rpms/xapi.git /var/lib/mock/v8.3-u-asultanov2-9885-28600/root/chroot_tmpdir/scmroot/xapi
Cloning into '/var/lib/mock/v8.3-u-asultanov2-9885-28600/root/chroot_tmpdir/scmroot/xapi'...
$ git fetch origin 5658fa2464db6f683fa0578dd7fbe7b1759d5d62:KOJI_FETCH_HEAD
From https://github.com/xcp-ng-rpms/xapi
 * [new ref]         5658fa2464db6f683fa0578dd7fbe7b1759d5d62 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 5658fa2 bump release for test build