Mayavi crashes when applying data_set_clip to points3d.

Dear mayavi users,

I would like to use `data_set_clip` in order to remove everything outside a bounding box after `mlab.points3d` plot.
I have tried, this example, based on `test_points3d`
```python
t = np.linspace(0, 1, 5)
x = np.cos(t)
y = np.sin(t)
z = t
s = mlab.points3d(x, y, z)
clip = mlab.pipeline.data_set_clipper(s)
mlab.show()
```
mayavi crashes and I get:
> 2020-11-12 10:16:11.218 ( 1,426s) [ A0CF5700] vtkPolyData.cxx:961 ERR| vtkPolyData (0x562c090b1340): Error while constructing cell map: Invalid cell size for polys.

I get the same message if the `data_set_clipper` is added from the gui.

All tried examples from mlab.test_* run without problem. Have you an idea on where I am wrong ?
Have you an idea of workaround to interactively hide points ?

It seems to be linked to `points3d`, since
```python
x, y = np.meshgrid(np.linspace(0,1, 20),
np.linspace(0,1, 20))
z = x*x + y*y
s = mlab.mesh(x, y, z)
clip = mlab.pipeline.data_set_clipper(s)
```
draw the clip box without error (to have a fully functional clipper, it requires `add_filter` methods and to play with the surfaces visibilities).

I have a fresh mayavi install from conda
mayavi 4.7.2,
vtk 9.0.1
python 3.9.4,
ubuntu 20.04

Thanks,

Benoit