Fix/attribute error (#1812)

* refactor : delete useless messages.json messages

* Update msg_stack.py

* Update msg_stack.py

* buf fix #1809
AttributeError

* buf fix #1809
AttributeError

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Co-authored-by: mengziyi.mzy <mengziyi.mzy@alibaba-inc.com>
Co-authored-by: Yufan Song <33971064+yufansong@users.noreply.github.com>

opendevin/server/session/msg_stack.py

@@ -99,7 +99,7 @@ class MessageStack:
                 new_data = {}
                 for sid, msgs in data.items():
                     if sid != del_sid:
-                        new_data[sid] = msgs
+                        new_data[sid] = [Message.from_dict(msg) for msg in msgs]
                 # Move the file pointer to the beginning of the file to overwrite the original contents
                 file.seek(0)
                 # clean previous content