Remove unused import

Author: roberth

src/Options/Applicative/Help/Core.hs

@@ -24,7 +24,7 @@ import Control.Monad (guard)
 import Data.Function (on)
 import Data.List (sort, intersperse, groupBy)
 import Data.Foldable (any, foldl')
-import Data.Maybe (maybeToList, catMaybes, fromMaybe)
+import Data.Maybe (catMaybes, fromMaybe)
 #if !MIN_VERSION_base(4,8,0)
 import Data.Monoid (mempty)
 #endif