Add more web test cases (#3702)

### What problem does this PR solve?

Test cases about dataset

### Type of change

- [x] Other (please describe): test cases

---------

Signed-off-by: jinhai <haijin.chn@gmail.com>

rag/utils/infinity_conn.py

@@ -310,7 +310,9 @@ class InfinityConnection(DocStoreConnection):
             table_name = f"{indexName}_{knowledgebaseId}"
             table_instance = db_instance.get_table(table_name)
             kb_res = table_instance.output(["*"]).filter(f"id = '{chunkId}'").to_pl()
-            df_list.append(kb_res)
+            if len(kb_res) != 0 and kb_res.shape[0] > 0:
+                df_list.append(kb_res)
+
         self.connPool.release_conn(inf_conn)
         res = concat_dataframes(df_list, ["id"])
         res_fields = self.getFields(res, res.columns)