[QuickCheck] QuickCheck 2.7.1 test suite is broken

[Peter Simons]

Hi,

according to the Cabal file, the test suite for QuickCheck 2.7.1
requires QuickCheck 2.7 to build. Thus, the build fails:

  http://hydra.cryp.to/build/43567/nixlog/1/raw

I hope this helps,
Peter