Allow zlib-0.7

(cherry picked from commit 8674b74d)

cabal-install/cabal-install.cabal

@@ -229,7 +229,7 @@ library
         stm        >= 2.0      && < 2.6,
         tar        >= 0.5.0.3  && < 0.7,
         time       >= 1.5.0.1  && < 1.13,
-        zlib       >= 0.5.3    && < 0.7,
+        zlib       >= 0.5.3    && < 0.8,
         hackage-security >= 0.6.2.0 && < 0.7,
         text       >= 1.2.3    && < 1.3 || >= 2.0 && < 2.2,
         parsec     >= 3.1.13.0 && < 3.2,