Fix: vtkPolyDataNormals not correctly orienting normals

Rupert Nashrequested to merge
rupertnash/vtk:polydatanormals into master

This is my attempt at fixing #18270 (closed)

I have (of course) added a test that fails without my fix, but I'm unsure if I've done it the "VTK way" such that it will hook into your CI properly.

@mwestphal kindly offered an initial review :)

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