fix(polys): fix pickling of poly objects for Python 3.11

This is needed after the changes in

  python/cpython#70766

Since object now has a __getstate__ method we need to make sure not to
call it with any arguments. Probably the __getstate__ methods can be
simplified (or removed?) in light of the cpython changes but for now
this is a quick fix to restore previous behaviour.

Author: oscarbenjamin

sympy/polys/polyutils.py

@@ -470,7 +470,7 @@ def __getstate__(self, cls=None):
 
         # Get all data that should be stored from super classes
         for c in cls.__bases__:
-            if hasattr(c, "__getstate__"):
+            if d is not object and hasattr(c, "__getstate__"):
                 d.update(c.__getstate__(self, c))
 
         # Get all information that should be stored from cls and return the dict