hlint-3.2.4: tests/flag-no-summary.test

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RUN tests/flag-no-summary1.hs --no-summary
FILE tests/flag-no-summary1.hs
main = map f $ map g xs
OUTPUT
tests/flag-no-summary1.hs:1:8-23: Suggestion: Use map once
Found:
  map f $ map g xs
Perhaps:
  map (f . g) xs

EXIT 1
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RUN tests/flag-no-summary2.hs --no-summary
FILE tests/flag-no-summary2.hs
main = return ()
OUTPUT
EXIT 0