$ git clone -n https://github.com/xcp-ng-rpms/xapi.git /var/lib/mock/v8.3-u-gtn1-9867-28587/root/chroot_tmpdir/scmroot/xapi
Cloning into '/var/lib/mock/v8.3-u-gtn1-9867-28587/root/chroot_tmpdir/scmroot/xapi'...
$ git fetch origin 46cd5f0426adcb5469f89884f787cf89d0fa55be:KOJI_FETCH_HEAD
From https://github.com/xcp-ng-rpms/xapi
 * [new ref]         46cd5f0426adcb5469f89884f787cf89d0fa55be -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 46cd5f0 bump release for test build