fix(core): don't cache the possible relation entities

The entities types a relation can point to can be changed at any time,
so they should not be cached.

Closes: #914

apis_core/utils/helpers.py

@@ -1,5 +1,4 @@
 import difflib
-import functools
 import importlib
 import inspect
 import itertools
@@ -20,7 +19,6 @@
 from django_tables2 import RequestConfig
 
 
-@functools.lru_cache
 def get_classes_with_allowed_relation_from(
     entity_name: str,
 ) -> list[object]: