improve matching of implementation accuracy

[bat52]

cadquery and solidpython .stl output files are generally much bigger than trimesh. This is due to the different default accuracy settings.

Particularly,

• 'T-splinerev.stl' (trimesh): ~80kB
• 'C-splinerev.stl' (cadquery) : ~900kB
• 'S-splinerev.stl' (solidpython): ~200kB.

It can be seen by visual inspection that this is related to different accuracy on the output shape.
Similar differences are visible for 'rndrod'.

This results in an overall file size of the default output of:

• trimesh: 2.2 MB
• blender: 2.3MB
• solidpython: 8.4MB
• cadquery: 13.3MB

I think we should try to reduce accuracy for solidpython and cadquery.

[bat52]

this can now routinely be checked looking at test_report.csv and/or test_report.xlsx, following this commit bat52@364168c