refactor: rag storage refactor (#2434)

examples/rag/simple_rag_retriever_example.py

@@ -76,14 +76,16 @@ def _create_vector_connector():
     """Create vector connector."""
     config = ChromaVectorConfig(
         persist_path=PILOT_PATH,
+    )
+
+    return ChromaStore(
+        config,
         name="embedding_rag_test",
         embedding_fn=DefaultEmbeddingFactory(
             default_model_name=os.path.join(MODEL_PATH, "text2vec-large-chinese"),
         ).create(),
     )
 
-    return ChromaStore(config)
-
 
 with DAG("simple_sdk_rag_retriever_example") as dag:
     vector_store = _create_vector_connector()