Relax build-deps to allow upcoming `array-0.5.0.0`

Signed-off-by: Herbert Valerio Riedel <hvr@gnu.org>

haskell98.cabal

@@ -23,7 +23,7 @@ Library
                     old-time    >= 1.0 && < 1.2,
                     old-locale  >= 1.0 && < 1.1,
                     process     >= 1.0 && < 1.3,
-                    array       >= 0.3 && < 0.5,
+                    array       >= 0.3 && < 0.6,
                     time        >= 1.2 && < 1.5
     exposed-modules:
         -- Haskell 98