nixos/portunus: fix dangling service files for dex

    };

    systemd.services = {

      dex.serviceConfig = mkIf cfg.dex.enable {

      dex = mkIf cfg.dex.enable {

        serviceConfig = {

          # `dex.service` is super locked down out of the box, but we need some

          # place to write the SQLite database. This creates $STATE_DIRECTORY below

          # /var/lib/private because DynamicUser=true, but it gets symlinked into

          # /var/lib/dex inside the unit

          StateDirectory = "dex";

        };

      };

      portunus = {

        description = "Self-contained authentication service";