Fixed #33984 -- Reverted "Fixed #32980 -- Made models cache related managers."

This reverts 4f8c7fd9d91b35e2c2922de4bb50c8c8066cbbc6 and adds
two regression tests:
- test_related_manager_refresh(), and
- test_create_copy_with_m2m().

Thanks joeli for the report.

1 files changed, 0 insertions, 8 deletions

diff --git a/django/contrib/contenttypes/fields.py b/django/contrib/contenttypes/fields.py
index 5b327b6ae4..bb93aa5d1e 100644
--- a/django/contrib/contenttypes/fields.py
+++ b/django/contrib/contenttypes/fields.py
@@ -552,14 +552,6 @@ class ReverseGenericManyToOneDescriptor(ReverseManyToOneDescriptor):
             self.rel,
         )
 
-    @cached_property
-    def related_manager_cache_key(self):
-        # By default, GenericRel instances will be marked as hidden unless
-        # related_query_name is given (their accessor name being "+" when
-        # hidden), which would cause multiple GenericRelations declared on a
-        # single model to collide, so always use the remote field's name.
-        return self.field.get_cache_name()
-
 
 def create_generic_related_manager(superclass, rel):
     """