fix Werror

Author: rnjtranjan

test/Streamly/Test/Data/Stream/Top.hs

@@ -1,7 +1,7 @@
 module Main (main)
     where
 
-import Data.List (intersect, sort, union, (\\))
+import Data.List (intersect, sort, (\\))
 import Test.QuickCheck
     ( Gen
     , Property