`gh auth refresh` exists to make it simpler for users to refresh their tokens on expiration/scope mismatch, but help messages only suggest using it in limited scenarios, and not in a common case of a token expiring and the user receiving a 401 error. Now, the auth flow will detect this case, and for refreshable tokens (namely, tokens created by logging in with `gh auth login` in the first place), it will suggest using `gh auth refresh` for these cases.
