$ git clone -n https://github.com/xcp-ng-rpms/xcp-ng-release.git /var/lib/mock/v8.3-u-stormi2-9493-28226/root/chroot_tmpdir/scmroot/xcp-ng-release
Cloning into '/var/lib/mock/v8.3-u-stormi2-9493-28226/root/chroot_tmpdir/scmroot/xcp-ng-release'...
$ git fetch origin 3746ab7eef8f194e34f9031936371534922c52f0:KOJI_FETCH_HEAD
From https://github.com/xcp-ng-rpms/xcp-ng-release
 * [new ref]         3746ab7eef8f194e34f9031936371534922c52f0 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 3746ab7 bump release for test build