Revert "MNT: Added an error for comparison of multi-properties if the property...

Revert "MNT: Added an error for comparison of multi-properties if the property is present several times only in the first argument"

This reverts commit 225e3296.

src/linkahead/apiutils.py

@@ -342,17 +342,8 @@ def compare_entities(old_entity: Entity,
 
     # we have not yet compared properties that do not exist in old_entity
     for prop in new_entity.properties:
-        # check how often the property appears in old_entity
-        num_old_prop = len([0 for p in old_entity.properties
-                            if p.name.lower() == prop.name.lower()])
-        if num_old_prop == 0:
-            # property is only present in new_entity - add to diff
+        if len([0 for p in old_entity.properties if p.name.lower() == prop.name.lower()]) == 0:
             newdiff["properties"][prop.name] = {}
-        if num_old_prop > 1:
-            # Check whether the property is present multiple times in old_entity
-            # and raise error - result would be incorrect
-            raise NotImplementedError(
-                "Comparison not implemented for multi-properties.")
 
     # compare parents
     # ToDo: Compare using filter function, compare inheritance level for RTs