Creating the API key before setting up billing doesn't work

[felixbade]

https://community.openai.com/t/api-keys-created-before-setting-up-billing-dont-work/173043

This is an API issue, but Assistant should take this into account somehow, because this is a very common problem with new users.

[felixbade]

Assistant could detect quota error and suggest to the user that they might need to create a new API token.