cabal: Bump xmonad dependency

Author: slotThe

xmonad-contrib.cabal

@@ -65,7 +65,7 @@ library
                    mtl >= 1 && < 3,
                    unix,
                    X11 >= 1.10 && < 1.11,
-                   xmonad >= 0.16.99999 && < 0.18,
+                   xmonad >= 0.16.99999 && < 0.19,
                    utf8-string,
                    deepseq
     default-language: Haskell2010
@@ -488,7 +488,7 @@ test-suite tests
                , unix
                , utf8-string
                , deepseq
-               , xmonad >= 0.16.9999 && < 0.18
+               , xmonad >= 0.16.9999 && < 0.19
   cpp-options: -DTESTING
   ghc-options: -Wall -Wno-unused-do-bind
   default-language: Haskell2010