Fix CircleCI build
Fix CircleCI build

Summary:
The setup script now carries the logic to avoid re-fetching the SDK, but makes
sure we install newer versions of the tools when necessary - which it currently
doesn't.

Reviewed By: marco-cova

Differential Revision: D5132552

fbshipit-source-id: 192f014f6dab670434f9a3993eccd4c64e8ec9f2

facebook/litho,facebook/litho,facebook/litho,facebook/litho,facebook/litho,facebook/litho