lxcfs: 6.0.3 -> 6.0.4

https://discuss.linuxcontainers.org/t/lxcfs-6-0-4-lts-has-been-released/23389
https://github.com/lxc/lxcfs/releases/tag/v6.0.4

Author: adamcstephens

pkgs/by-name/lx/lxcfs/package.nix

@@ -17,13 +17,13 @@
 
 stdenv.mkDerivation rec {
   pname = "lxcfs";
-  version = "6.0.3";
+  version = "6.0.4";
 
   src = fetchFromGitHub {
     owner = "lxc";
     repo = "lxcfs";
-    rev = "v${version}";
-    hash = "sha256-+Xlx1E6ggB/Vx3yOJGgh4UfEvaVyT7uOttaxelDA7Iw=";
+    tag = "v${version}";
+    hash = "sha256-jmadClC/3nHfNL+F/gC5NM6u03OE9flEVtPU28nylw4=";
   };
 
   patches = [