testing/freecad: reenable all tests

This MR patches py3-pivy so that it works with python 3.10 and doesn't cause segmentation faults when used with the various FreeCAD workbenches. Most of the tests pass, but some of the ones that don't (one in mesh test app that seems to be a minor incompatibility problem, and the emery FEM solver which still needs to be updated for python 3.10) have been disabled through a new patch.