Add check for invalid extents when checking a field

[pspoerri]

    gt_verification::boundary_extent boundaryK() const noexcept {
        return makeBoundaryExtent(0, 0, 0, 0, 0, 1);
    }
    collection_.register_output_and_reference_field("w", w_out, env_.boundaryK());

should throw an error if used with a field that has no boundaries in k.