$ git clone -n https://github.com/xcp-ng-rpms/xapi.git /var/lib/mock/v8.3-u-asultanov2-11376-29684/root/chroot_tmpdir/scmroot/xapi
Cloning into '/var/lib/mock/v8.3-u-asultanov2-11376-29684/root/chroot_tmpdir/scmroot/xapi'...
$ git fetch origin 8e858f9daac600c3b57aaa7f25d82738ef9dca85:KOJI_FETCH_HEAD
From https://github.com/xcp-ng-rpms/xapi
 * [new ref]         8e858f9daac600c3b57aaa7f25d82738ef9dca85 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 8e858f9 bump release for test build