rsshub: add update script

Signed-off-by: Dan Xin <davinci42.cn@gmail.com>

Author: DaVinci42

pkgs/by-name/rs/rsshub/package.nix

@@ -2,6 +2,7 @@
   lib,
   fetchFromGitHub,
   makeBinaryWrapper,
+  nix-update-script,
   nodejs,
   pnpm_10,
   patchelf,
@@ -64,6 +65,8 @@ stdenv.mkDerivation (finalAttrs: {
       --add-flags "$out/lib/rsshub/dist/index.mjs"
   '';
 
+  passthru.updateScript = nix-update-script { extraArgs = [ "--version=branch" ]; };
+
   meta = {
     description = "RSS feed generator";
     longDescription = ''