Add example to wrap vtkFilter into Python

The ComplexModuleArchitecture plugin example adds a VTK filter, and its Proxy.

Loading the resulting .so allows to create the filter (proxy), either from the GUI menus or from python shell.

Then we want to create the actual VTK filter in python (e.g. vtkMyOtherElevationFilter() in a ProgrammableFilter).

Based on https://gitlab.kitware.com/vtk/vtk/-/tree/master/Examples/Modules/Wrapping?ref_type=heads , this adds the CMake code that will allow that. Note vtk/vtk#19531 issue, impacting testing this feature on windows.

Topic-rename: plugin-module-python-wrapping-example