Small overlap between magnets andblanket rear wall

[shimwell]

When testing the next export_html with facetets on the reactor models I noticed a few potential overlaps.

It appears that the faceteted spline that makes up the rear surface of the blanket overlaps with the TF coils as shown in the screen shots below

To reproduce this error run the example that produces html file outputs

cd ~/paramak/examples/example_parametric_reactors
python make_all_reactors.py
firefox SegmentedBlanketBallReactor/reactor.html
firefox BallReactor/reactor.html

I can't quite see this overlap when I inspect the CAD files (stp) files produced but perhaps it would be wise to put a small gap in between these two shapes.