Prepare local and staging environments on Nango Cloud

[themarolt]

Currently we have everything prepared for production on Prod Nango Cloud env which is not ideal since we can't test this locally or on production so we have to prepare a bunch of github-token connections like we have on production on other two envs so we can test this key rotation locally/on staging as well.

This was already prepared by Joan and in the docs beyond that they are just auth tokens from different users that we gonna use for key rotation I don't have much details so estimation is kinda hard here - I assume it's pretty easy once explained.