switch exception type

#include "csg_cgal_helper.hpp"

#include <stdexcept>

#include "csg_exception.hpp"

#include <CGAL/AABB_face_graph_triangle_primitive.h>

#include <CGAL/AABB_traits.h>

    for (const auto &face : m_faces) {

      B.begin_facet();

      if (!B.test_facet(face.begin(), face.end()))

        throw std::runtime_error(

        throw csg::Exception(

            "Polyhedron builder",

            "Unable to create the polyhedron. test_facet failed. Check input!");

      for (const auto &p_index : face) {