cad/freecad: update to 1.1 (rc3)
Announcement: https://github.com/FreeCAD/FreeCAD/releases/tag/1.1rc3
This allows for "easy" unbreaking of the port against VTK 9.6, and at
this point I belive the risk of using this RC is less than the risk
of adapting the vtk-9.6-compat patches.