Fix misspelled 'answer' in Graph-RAG example prompt

[munichpavel]

Fix typo in Graph RAG Example OpenAI prompt system message

Changes

anwser -> answer

How I tested this

Visual inspection.

Notes

Just housekeeping. I seriously doubt there is any performance change, though if you wanted to test for any performance change, it would be a good example of (blog self-promotion alert) how Prompts just blew up your configuration space (and what to do about it)

Checklist

• PR has an informative and human-readable title (this will be pulled into the release notes)
• Changes are limited to a single goal (no scope creep)
• Code passed the pre-commit check & code is left cleaner/nicer than when first encountered.
• Any change in functionality is tested
• New functions are documented (with a description, list of inputs, and expected output)
• Placeholder code is flagged / future TODOs are captured in comments
• Project documentation has been updated if adding/changing functionality.

[elijahbenizzy]

Thank you!