$ git clone -n https://github.com/xcp-ng-rpms/xapi.git /var/lib/mock/v8.3-u-asultanov2-9304-28070/root/chroot_tmpdir/scmroot/xapi
Cloning into '/var/lib/mock/v8.3-u-asultanov2-9304-28070/root/chroot_tmpdir/scmroot/xapi'...
$ git fetch origin db5bfe4b7c1fd6492f08ee832eb2d3a6bbc1950e:KOJI_FETCH_HEAD
From https://github.com/xcp-ng-rpms/xapi
 * [new ref]         db5bfe4b7c1fd6492f08ee832eb2d3a6bbc1950e -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at db5bfe4 bump release for test build