Describe the feature or problem you’d like to solve

When you log in with gh auth login, most of the options can be set via flags.
However, skipping the message generates a new SSH key is impossible.

? Generate a new SSH key to add to your GitHub account? (Y/n) 

Proposed solution

Skip that message with --skip-ssh-key flag, for example.

Additional context

With this flag, you can log in with no selection.

gh auth login -h='GitHub.com' -p='SSH' --skip-ssh-key -w