volnoti: add platform assert

modules/misc/news.nix

@@ -2136,6 +2136,7 @@ in
 
       {
         time = "2021-07-14T20:06:18+00:00";
+        condition = hostPlatform.isLinux;
         message = ''
           A new module is available: 'services.volnoti'.
         '';

modules/services/volnoti.nix

@@ -23,7 +23,13 @@ in {
   };
 
   config = mkIf cfg.enable {
+    assertions = [
+      (lib.hm.assertions.assertPlatform "services.volnoti" pkgs
+        lib.platforms.linux)
+    ];
+
     home.packages = [ cfg.package ];
+
     systemd.user.services.volnoti = {
       Unit = { Description = "volnoti"; };