fix error exporting schedule of rates #4723

Issue occurred when cost item would have no quantities but had controlled objects with quantities.

1) just added a check to ensure that cost_item.CostQuantities are present
2) removed possible None return value in get_cost_item_quantity as it actually will break process_cost_data and it's never used anywhere else
3) has_changed_name was unused
4) fix possible similar issue in cost.data (though _get_object_quantities method is unused)

src/blenderbim/blenderbim/bim/module/cost/data.py

@@ -202,6 +202,9 @@ class CostSchedulesData:
     def _get_object_quantities(cls, cost_item, element):
         if not element.is_a("IfcObject"):
             return []
+        cost_quantities = cost_item.CostQuantities
+        if not cost_quantities:
+            return []
         results = []
         for relationship in element.IsDefinedBy:
             if not relationship.is_a("IfcRelDefinesByProperties"):
@@ -210,7 +213,7 @@ class CostSchedulesData:
             if not qto.is_a("IfcElementQuantity"):
                 continue
             for prop in qto.Quantities:
-                if prop in cost_item.CostQuantities or []:
+                if prop in cost_quantities:
                     results.append(prop.id())
         return results