Fix Faraday warning about basic_auth deprecation

[vnorguet]

Context

Faraday has deprecated Faraday::Connection#basic_auth and show a warning message when running the code

Warning message

WARNING: `Faraday::Connection#basic_auth` is deprecated; it will be removed in vers`ion 2.0.
While initializing your connection, use `#request(:basic_auth, ...)` instead.
See https://lostisland.github.io/faraday/middleware/authentication for more usage info.

What does this PR do

Fix warning message by updating related code to the latest version

[benlings]

@ErebusBat Can this be merged? I'd rather not make another fork to combine both yours and @vnorguet 's...