Fix conversation bug in agent session (#4078)

### What problem does this PR solve?

Fix conversation bug in agent session

### Type of change

- [x] Bug Fix (non-breaking change which fixes an issue)

---------

Co-authored-by: liuhua <10215101452@stu.ecun.edu.cn>

sdk/python/ragflow_sdk/modules/session.py

@@ -30,6 +30,8 @@ class Session(Base):
             if line.startswith("data:"):
                 json_data = json.loads(line[5:])
                 if json_data["data"] is not True:
+                    if json_data["data"].get("running_status"):
+                        continue
                     answer = json_data["data"]["answer"]
                     reference = json_data["data"]["reference"]
                     temp_dict = {