$ git clone -n https://github.com/xcp-ng-rpms/xapi.git /var/lib/mock/v8.3-u-asultanov2-11373-29677/root/chroot_tmpdir/scmroot/xapi
Cloning into '/var/lib/mock/v8.3-u-asultanov2-11373-29677/root/chroot_tmpdir/scmroot/xapi'...
$ git fetch origin 81ca9f11bcf734be025f865824421ea1693c0496:KOJI_FETCH_HEAD
From https://github.com/xcp-ng-rpms/xapi
 * [new ref]         81ca9f11bcf734be025f865824421ea1693c0496 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 81ca9f1 bump release for test build