1ffbeaf0

By: Tom Sydney Kerckhove <syd@cs-syd.eu>

Use addTestToolDepend(s) instead of overrideCabal testDepends

testDepends is for Haskell library deps; postgres/redis/sqitch are
binaries that need to be on $PATH at test runtime, which is what
testToolDepends expresses. addTestToolDepend(s) is the dedicated helper
and also makes these lines a lot shorter.