Update OpenAI model in llm adventure game example

[goutamk09]

Testing

• Ran the llm adventure game example locally after updating the model
• Application starts and executes normally (Graphviz rendering requires system Graphviz)

Screenshots are attached in the PR comments.

[goutamk09]

HI @skrawcz, Tested locally after updating the model.

Ran:
python application.py

The app starts and runs; Graphviz error on Windows is expected and unrelated to the model change.

Screenshots attached below.