feat: add evaluation service module for RAG and Agent (#2070)

dbgpt/rag/operators/evaluation.py

@@ -54,7 +54,7 @@ class RetrieverEvaluatorOperator(JoinOperator[List[EvaluationResult]]):
                     contexts=contexts,
                     passing=result.passing,
                     raw_dataset=raw_dataset,
-                    metric_name=metric.name,
+                    metric_name=metric.name(),
                 )
             )
         return results