$ git clone -n https://github.com/xcp-ng-rpms/xapi.git /var/lib/mock/v8.3-u-abourgeois1-9610-28345/root/chroot_tmpdir/scmroot/xapi
Cloning into '/var/lib/mock/v8.3-u-abourgeois1-9610-28345/root/chroot_tmpdir/scmroot/xapi'...
$ git fetch origin c8a1b9fd49fd2373c50c02a5e0a65c5624d7fc91:KOJI_FETCH_HEAD
From https://github.com/xcp-ng-rpms/xapi
 * [new ref]         c8a1b9fd49fd2373c50c02a5e0a65c5624d7fc91 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at c8a1b9f bump release for test build