Fix CORE API -> Rattail datasync for ProductCost

rattail_corepos/datasync/rattail.py

@@ -108,6 +108,14 @@ class FromCOREAPIToRattail(NewDataSyncImportConsumer):
                 self.process_change(session, self.importers['Product'],
                                     host_object=product)
 
+        # sync all ProductCost-related changes
+        types = [
+            'VendorItem',
+        ]
+        for change in [c for c in changes if c.payload_type in types]:
+            # normal logic works fine here
+            self.invoke_importer(session, change)
+
     def get_host_object(self, session, change):
         if change.payload_type == 'Member':
             return self.api.get_member(change.payload_key)