modules/useable: remove superfluous plasma-thunderbolt addition

already taken over by plasma6 module: https://github.com/NixOS/nixpkgs/blob/nixos-24.05/nixos/modules/services/desktop-managers/plasma6.nix

nix/nixos-modules/useable.nix

@@ -55,14 +55,10 @@ in
     environment.systemPackages =
       with pkgs;
       let
-        inherit (lib.lists) flatten optional optionals;
+        inherit (lib.lists) flatten optionals;
       in
       flatten [
 
-        (optional (
-          config.services.hardware.bolt.enable && config.services.desktopManager.plasma6.enable
-        ) kdePackages.plasma-thunderbolt) # TODO upstream
-
         (optionals config.hardware.bluetooth.enable [
           bluetuith
         ])