Blender Git Loki

Fix T51072: The reference of a pyobject may be being overwritten in `bm_mesh_remap_cd_update`

In this case the Pyobject gets lost from pybm, and bm.free() does not invalidate the PyElem.
This will cause the destructor of python to read invalid memory and crash.

The solution is to make a copy of the pyobjects pointers before overwriting.