Fix comparison on tarballs
Fix comparison on tarballs

If the tarballs didn't contain the exact same entries, in the exact same order,
then `equalTarBall` would report lots of superfluous errors due to a call to
`mergeBy` on unsorted lists.


agrafix/hackage-server,snoyberg/hackage-server,grayjay/hackage-server,chrisdotcode/hackage-server,edsko/hackage-server,tkvogt/hackage-server,edsko/hackage-server,tkvogt/hackage-server,haskell-infra/hackage-server,dzackgarza/hackage-server,snoyberg/hackage-server,erantapaa/hackage-server,erantapaa/hackage-server,grayjay/hackage-server,agrafix/hackage-server,ocharles/hackage-server,dzackgarza/hackage-server,ocharles/hackage-server,chrisdotcode/hackage-server