fix(#64): cartesian product in reln reflection to non-versioned classes

In many-to-many relationships when one of the classes is not versioned,
we were not including the secondaryjoin in the filter criteria leading
to a cartesian product.

Author: winwinashwin

sqlalchemy_history/relationship_builder.py

@@ -83,7 +83,12 @@ def criteria(self, obj):
                 return self.many_to_one_criteria(obj)
         else:
             reflector = VersionExpressionReflector(obj, self.property)
-            return reflector(self.property.primaryjoin)
+            criteria = reflector(self.property.primaryjoin)
+
+            # For many-to-many relationships, we also need to include the secondary join
+            if direction.name == "MANYTOMANY" and self.property.secondaryjoin is not None:
+                criteria = sa.and_(criteria, reflector(self.property.secondaryjoin))
+            return criteria
 
     def many_to_many_criteria(self, obj):
         """Returns the many-to-many query.