screenly-cli: add nix-update-script

pkgs/by-name/sc/screenly-cli/package.nix

@@ -6,6 +6,7 @@
 , openssl
 , rustPlatform
 , stdenv
+, nix-update-script
 }:
 
 rustPlatform.buildRustPackage rec {
@@ -35,6 +36,8 @@ rustPlatform.buildRustPackage rec {
     darwin.apple_sdk.frameworks.SystemConfiguration
   ];
 
+  passthru.updateScript = nix-update-script { };
+
   meta = {
     description = "Tools for managing digital signs and screens at scale";
     homepage = "https://github.com/Screenly/cli";