Fix 0.2 Quickstart example llm_config issue (#4060)

* fix bug in getting started guide for 0.2 #2038

* remove uneeded submodule

* remove uneeded submodule

* remove unecessary file

Author: victordibia

website/docs/Getting-Started.mdx

@@ -45,7 +45,7 @@ pip install autogen-agentchat~=0.2
 import os
 from autogen import AssistantAgent, UserProxyAgent
 
-llm_config = {"model": "gpt-4", "api_key": os.environ["OPENAI_API_KEY"]}
+llm_config = { "config_list": [{ "model": "gpt-4", "api_key": os.environ.get("OPENAI_API_KEY") }] }
 assistant = AssistantAgent("assistant", llm_config=llm_config)
 user_proxy = UserProxyAgent("user_proxy", code_execution_config=False)