Adding GPT 4o to Github Copilot CLI

### Describe the feature or problem you'd like to solve

GPT 4o is a wonderful model that is present in Copilot Chat, and in the Github Copilot extension for VS Code but is currently missing in Github CLI.

### Proposed solution

Add GPT 4o access to Copilot CLI

### Example prompts or workflows

_No response_

### Additional context

_No response_