Fix type in test
Fix type in test

Summary: fail isn't a thing

Reviewed By: passy

Differential Revision: D16335797

fbshipit-source-id: c2f07b722424f540e6eb1a4cd423397ec1fe545c

facebook/flipper,facebook/flipper,facebook/flipper,facebook/flipper,facebook/flipper,facebook/flipper,facebook/flipper,facebook/flipper,facebook/flipper,facebook/flipper,facebook/flipper