Provide initial values to exitcode, exitcode2str and logs

[marcos-venicius]

When using gpt-3.5-turbo-1106 i got the error bellow

User_Proxy (to chat_manager):

Find a latest paper about gpt-4 on arxiv and find its potential applications in software

--------------------------------------------------------------------------------

>>>>>>>> USING AUTO REPLY...
Traceback (most recent call last):
  File "/home/marcos_souza/Projects/auto-gen/2/./main.py", line 46, in <module>
    user_proxy.initiate_chat(
  File "/home/marcos_souza/.local/lib/python3.10/site-packages/flaml/autogen/agentchat/conversable_agent.py", line 521, in initiate_chat
    self.send(self.generate_init_message(**context), recipient, silent=silent)
  File "/home/marcos_souza/.local/lib/python3.10/site-packages/flaml/autogen/agentchat/conversable_agent.py", line 324, in send
    recipient.receive(message, self, request_reply, silent)
  File "/home/marcos_souza/.local/lib/python3.10/site-packages/flaml/autogen/agentchat/conversable_agent.py", line 452, in receive
    reply = self.generate_reply(messages=self.chat_messages[sender], sender=sender)
  File "/home/marcos_souza/.local/lib/python3.10/site-packages/flaml/autogen/agentchat/conversable_agent.py", line 767, in generate_reply
    final, reply = reply_func(self, messages=messages, sender=sender, config=reply_func_tuple["config"])
  File "/home/marcos_souza/.local/lib/python3.10/site-packages/flaml/autogen/agentchat/groupchat.py", line 118, in run_chat
    reply = speaker.generate_reply(sender=self)
  File "/home/marcos_souza/.local/lib/python3.10/site-packages/flaml/autogen/agentchat/conversable_agent.py", line 767, in generate_reply
    final, reply = reply_func(self, messages=messages, sender=sender, config=reply_func_tuple["config"])
  File "/home/marcos_souza/.local/lib/python3.10/site-packages/flaml/autogen/agentchat/conversable_agent.py", line 635, in generate_code_execution_reply
    return True, f"exitcode: {exitcode} ({exitcode2str})\nCode output: {logs}"
UnboundLocalError: local variable 'exitcode' referenced before assignment

This happens because the logs, exitcode and exitcode2str does not have an "initial value", so, when we not have messages no code is executed and the exitcode, logs and exitcode2str is not initiated, so, the code breaks as we can see above.

Why are these changes needed?

Related issue number

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• I've added tests (if relevant) corresponding to the changes introduced in this PR.
• I've made sure all auto checks have passed.

[marcos-venicius]

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[sonichi]

Could you move the discussion to https://github.com/microsoft/autogen ? AutoGen has been developed in its own repo since October.
And please try the latest version of pyautogen. This error shouldn't happen in my understanding.