haddock-2.14.3: enable test suite

https://github.com/NixOS/cabal2nix/pull/86

Changed files
+1 -1
pkgs
development
tools
documentation
haddock
+1 -1
pkgs/development/tools/documentation/haddock/2.14.3.nix
···
isExecutable = true;
buildDepends = [ Cabal deepseq filepath ghcPaths xhtml ];
testDepends = [ Cabal deepseq filepath hspec QuickCheck ];
-
doCheck = false;
+
preCheck = "unset GHC_PACKAGE_PATH";
meta = {
homepage = "http://www.haskell.org/haddock/";
description = "A documentation-generation tool for Haskell libraries";