[accounting_rjs_test] Fix test mock script bug

bt5/erp5_accounting_ui_test/SkinTemplateItem/portal_skins/erp5_accounting_ui_test/AccountingZuite_createReportAgedBalanceDataset.py

@@ -23,7 +23,7 @@ def get_object_by_title(portal_type, title):
     portal_type=portal_type,
     title=SimpleQuery(title=title, comparison_operator='='))
   if len(result) == 1:
-    return result.getObject()
+    return result[0].getObject()
   return None