[NixOS] Use dunst instead of notify-osd

nixos/xmonad.nix

@@ -33,6 +33,8 @@ makeEnable config "modules.xmonad" true  {
   ];
 
   home-manager.users = forEachUser {
+    imports = [ ./dunst.nix ];
+
     services.blueman-applet = {
       enable = true;
     };
@@ -42,11 +44,6 @@ makeEnable config "modules.xmonad" true  {
       package = inputs.imalison-taffybar.defaultPackage."${pkgs.system}";
     };
 
-    services.notify-osd = {
-      enable = true;
-      package = pkgs.notify-osd-customizable;
-    };
-
     services.kdeconnect = {
       enable = true;
       indicator = true;