nixos/unifi: always restart service

This allows the controller to restart when restoring from a backup

Author: qubitnano

nixos/modules/services/networking/unifi.nix

@@ -146,7 +146,7 @@ in
         Type = "notify";
         ExecStart = "${cmd} start";
         ExecStop = "${cmd} stop";
-        Restart = "on-failure";
+        Restart = "always";
         TimeoutSec = "5min";
         User = "unifi";
         UMask = "0077";