integrals do not work for simplices when overintegrating

[MTCam]

Using elementwise_integral or integral currently fails for simplices when vec arg lives on the quadrature domain. The observed error is:

>           approx_surface_area = actx.to_numpy(op.integral(dcoll, dd, ones_volm))

test_grudge.py:212: 
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _
../grudge/reductions.py:304: in integral
    dcoll, dd, vec * _apply_mass_operator(dcoll, dd, dd, ones)
../grudge/op.py:711: in _apply_mass_operator
    data=tuple(
../grudge/op.py:713: in <genexpr>
    reference_mass_matrix(
../grudge/op.py:691: in reference_mass_matrix
    return get_ref_mass_mat(out_element_group, in_element_group)
../../miniforge3/envs/pristine2/lib/python3.11/site-packages/pytools/__init__.py:1008: in new_inner
    result = inner(*args)
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _

out_grp = <meshmode.discretization.poly_element.QuadratureSimplexElementGroup object at 0x1341a2450>
in_grp = <meshmode.discretization.poly_element.QuadratureSimplexElementGroup object at 0x1341a2450>

    @keyed_memoize_in(
        actx, reference_mass_matrix,
        lambda out_grp, in_grp: (out_grp.discretization_key(),
                                 in_grp.discretization_key()))
    def get_ref_mass_mat(out_grp, in_grp):
        if out_grp == in_grp:
            return actx.freeze(
                actx.from_numpy(
>                   mp.mass_matrix(out_grp.basis_obj(), out_grp.unit_nodes)
                    )
                )
E           AttributeError: 'QuadratureSimplexElementGroup' object has no attribute 'basis_obj'

../grudge/op.py:673: AttributeError

The issue can be reproduced by using #364 :

pytest -k surface_area test_grudge.py