cosmic-files: add updateScript

pkgs/by-name/co/cosmic-files/package.nix

@@ -6,6 +6,7 @@
   just,
   libcosmicAppHook,
   glib,
+  nix-update-script,
 }:
 
 rustPlatform.buildRustPackage (finalAttrs: {
@@ -46,6 +47,15 @@ rustPlatform.buildRustPackage (finalAttrs: {
     "target/${stdenv.hostPlatform.rust.cargoShortTarget}/release/cosmic-files"
   ];
 
+  passthru.updateScript = nix-update-script {
+    extraArgs = [
+      "--version"
+      "unstable"
+      "--version-regex"
+      "epoch-(.*)"
+    ];
+  };
+
   meta = {
     homepage = "https://github.com/pop-os/cosmic-files";
     description = "File Manager for the COSMIC Desktop Environment";