perl-packages: Gtk2 1.2495 -> 1.2496

Upstream changes:
- Avoid registering a GType for GConnectFlags if not needed
- MANIFEST: added missing gtk-demo files

pkgs/top-level/perl-packages.nix

···
   };
 
   Gtk2 = buildPerlPackage rec {
-    name = "Gtk2-1.2495";
+    name = "Gtk2-1.2496";
     src = fetchurl {
       url = "mirror://cpan/authors/id/X/XA/XAOC/${name}.tar.gz";
-      sha256 = "1mpxkcy8j7r95z4g4xx6ggbgzaxj4zl0szz54y1k120z95rcgg3a";
+      sha256 = "1avn77m5hrdyy4k5sqgf870nsmykf6zlcn1haj8arjjl9yaxwic6";
     };
     buildInputs = [ ExtUtilsDepends ExtUtilsPkgConfig Pango pkgs.gtk2 ];
     meta = {