Remove duplicated language extensions from scaffolded cabal file

yesod/scaffold/project.cabal.cg

@@ -94,17 +94,6 @@ test-suite test
     main-is:           main.hs
     hs-source-dirs:    tests
     ghc-options:       -Wall
-    extensions:        TemplateHaskell
-                       QuasiQuotes
-                       OverloadedStrings
-                       NoImplicitPrelude
-                       CPP
-                       OverloadedStrings
-                       MultiParamTypeClasses
-                       TypeFamilies
-                       GADTs
-                       GeneralizedNewtypeDeriving
-                       FlexibleContexts
 
     build-depends: base
                  , ~project~

yesod/scaffold/tests/HomeTest.hs.cg

@@ -1,8 +1,8 @@
+{-# LANGUAGE OverloadedStrings #-}
 module HomeTest
     ( homeSpecs
     ) where
 
-import Import
 import Yesod.Test
 
 homeSpecs :: Specs