$ git clone -n https://src.fedoraproject.org/rpms/vdr-screenshot.git /var/lib/mock/f42-build-side-1-3512367-46069/root/chroot_tmpdir/scmroot/vdr-screenshot
Cloning into '/var/lib/mock/f42-build-side-1-3512367-46069/root/chroot_tmpdir/scmroot/vdr-screenshot'...
$ git fetch origin cb706d8d58a1c264a6baafecc758deef96b67182:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/vdr-screenshot
 * [new ref]         cb706d8d58a1c264a6baafecc758deef96b67182 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at cb706d8 Rebuilt for new VDR API version 2.7.4