Amend schedule with ai-code-review talk

- Update placeholder with link and overview to the generalization
of the chat-gpt-plugin with the new ai-code-review plugin.
- Added overview into hackathon-ai-code-review-plugin.md
- Added speakers.md section #trevorgetty.

Change-Id: I80e523e5cd901033db17fde6b3bf0cf29bf41cb8