Remove compiler warning (#351)

Author: EncodePanda

lib/Language/Haskell/Stylish/Step/SimpleAlign.hs

@@ -186,7 +186,7 @@ grhsToAlignable (S.L _ _)            = Nothing
 
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 step :: Maybe Int -> Config -> Step
-step maxColumns config@(Config {..}) = makeStep "Cases" $ \ls module' ->
+step maxColumns config = makeStep "Cases" $ \ls module' ->
     let changes
             :: (S.Located (Hs.HsModule Hs.GhcPs) -> [a])
             -> (a -> [[Alignable S.RealSrcSpan]])