[haskell-http-client] disable unused import warning in Core.hs (#4020)

Author: jonschoning

modules/openapi-generator/src/main/resources/haskell-http-client/Core.mustache

@@ -14,7 +14,7 @@ Module : {{baseModule}}.Core
 {-# LANGUAGE ScopedTypeVariables #-}
 {-# LANGUAGE TupleSections #-}
 {-# LANGUAGE TypeFamilies #-}
-{-# OPTIONS_GHC -fno-warn-name-shadowing -fno-warn-unused-binds #-}
+{-# OPTIONS_GHC -fno-warn-name-shadowing -fno-warn-unused-binds -fno-warn-unused-imports #-}
 
 module {{baseModule}}.Core where
 

samples/client/petstore/haskell-http-client/lib/OpenAPIPetstore/Core.hs

@@ -23,7 +23,7 @@ Module : OpenAPIPetstore.Core
 {-# LANGUAGE ScopedTypeVariables #-}
 {-# LANGUAGE TupleSections #-}
 {-# LANGUAGE TypeFamilies #-}
-{-# OPTIONS_GHC -fno-warn-name-shadowing -fno-warn-unused-binds #-}
+{-# OPTIONS_GHC -fno-warn-name-shadowing -fno-warn-unused-binds -fno-warn-unused-imports #-}
 
 module OpenAPIPetstore.Core where