Add nix-flatpak module, flake update.

nodes/hosts/common/configuration.nix

@@ -30,11 +30,4 @@
       experimental-features = nix-command flakes
     '';
   };
-
-  users.users = {
-    jay = {
-      description = "Jay Carter";
-      shell = pkgs.bash;
-    };
-  };
 }