Cannot overlay point set on image

## Summary

Passing an image and a point set that are in correspondence to an `itkwidgets.view` results in only the image being displayed.

## Expected behavior

In the 0.32.5 release calling `itkwidgets.view(image, point_sets=points)` would result in both the image and point set being overlaid in the 3D scene.

## Observed behavior

Image is shown but no points are visible in the scene. Overlay shows no evidence that point set is displayed.



## Versions

itkwidgets==1.0a22
itk==v5.3.0
notebook==6.1.6

## Platforms

Windows 10
Google Chrome browser

## Additional Notes

- The image I am trying to show has a non-identity direction matrix and depends on the fix in https://github.com/InsightSoftwareConsortium/itkwidgets/issues/596, therefore I cannot downgrade to 0.32.5.
- Could be related to https://github.com/InsightSoftwareConsortium/itkwidgets/issues/605. I cannot see points when I drag the scene around, but it is possible that they are simply very small.

cc @thewtex @PaulHax