Support hashable-1.4 (#324)

https://hackage.haskell.org/package/hashable-1.4.0.0/changelog

Author: sjakobi

unordered-containers.cabal

@@ -56,7 +56,7 @@ library
   build-depends:
     base >= 4.9 && < 5,
     deepseq >= 1.1,
-    hashable >= 1.0.1.1 && < 1.4
+    hashable >= 1.0.1.1 && < 1.5
 
   default-language: Haskell2010