bug/"This API key is invalid against the paid api" message may be incorrect

[awalker4]

The SuggestDefiningUrlIf401AfterErrorHook logs a suggestion to switch to the free api if you get back a 401. However, we don't check the url that was actually used. We should only log this if you are accessing serverless, and you get a 401. Otherwise, you could be correctly pointing to the free api and the key is really just invalid.