Remove tests which test Play CRSF system

It's a little redundant to test Play Framework features unless there's
special justification for doing so.
WIP

AuthActionTest removed because it's effectively testing
AuthenticatedBuilder now, which is tested within Play:

https://github.com/playframework/playframework/blob/9b33c199a/framework/src/play-integration-test/src/test/scala/play/it/auth/SecuritySpec.scala#L15