Lua marshalling: Remove unused language extensions

src/Text/Pandoc/Lua/Marshaling/AST.hs

@@ -1,7 +1,5 @@
 {-# OPTIONS_GHC -fno-warn-orphans #-}
 {-# LANGUAGE NoImplicitPrelude    #-}
-{-# LANGUAGE FlexibleInstances    #-}
-{-# LANGUAGE ScopedTypeVariables  #-}
 {-# LANGUAGE LambdaCase           #-}
 {- |
    Module      : Text.Pandoc.Lua.Marshaling.AST

src/Text/Pandoc/Lua/Marshaling/Context.hs

@@ -1,6 +1,4 @@
 {-# LANGUAGE NoImplicitPrelude    #-}
-{-# LANGUAGE FlexibleInstances    #-}
-{-# LANGUAGE ScopedTypeVariables  #-}
 {-# OPTIONS_GHC -fno-warn-orphans #-}
 {- |
    Module      : Text.Pandoc.Lua.Marshaling.Context

src/Text/Pandoc/Lua/Marshaling/List.hs

@@ -1,5 +1,5 @@
-{-# LANGUAGE FlexibleInstances #-}
 {-# LANGUAGE DeriveDataTypeable   #-}
+{-# LANGUAGE FlexibleInstances #-}
 {-# LANGUAGE MultiParamTypeClasses #-}
 {-# LANGUAGE NoImplicitPrelude    #-}
 {-# LANGUAGE UndecidableInstances #-}

src/Text/Pandoc/Lua/Marshaling/ReaderOptions.hs

@@ -1,8 +1,7 @@
-{-# LANGUAGE NoImplicitPrelude    #-}
-{-# LANGUAGE FlexibleInstances    #-}
-{-# LANGUAGE ScopedTypeVariables  #-}
-{-# LANGUAGE OverloadedStrings    #-}
 {-# LANGUAGE LambdaCase           #-}
+{-# LANGUAGE NoImplicitPrelude    #-}
+{-# LANGUAGE OverloadedStrings    #-}
+{-# LANGUAGE ScopedTypeVariables  #-}
 {-# OPTIONS_GHC -fno-warn-orphans #-}
 {- |
    Module      : Text.Pandoc.Lua.Marshaling.ReaderOptions