fix: remove redirected URLs (#41)

https://hacker-news.firebaseio.com/v0/ returns a 301 response and redirects to https://console.firebase.google.com/project/firebase-hacker-news/database/hacker-news/data/v0

This seems to be used to provide a more user friendly URL. Cran's view on 301 redirects is that the redirected URL should be used.

See https://r-pkgs.org/release.html#keeping-up-with-change for details