$ git clone -n https://github.com/xcp-ng-rpms/libempserver.git /var/lib/mock/v9.0-incoming-11270-29616/root/chroot_tmpdir/scmroot/libempserver
Cloning into '/var/lib/mock/v9.0-incoming-11270-29616/root/chroot_tmpdir/scmroot/libempserver'...
$ git fetch origin 1b6c61901885ec3f54bda576eb1dfb5a031b9ed4:KOJI_FETCH_HEAD
From https://github.com/xcp-ng-rpms/libempserver
 * [new ref]         1b6c61901885ec3f54bda576eb1dfb5a031b9ed4 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 1b6c619 Merge branch 'XS-9.0'