fix(desktop): add updater back to tauri features

[maxbrunet]

I'm trying to package DevPod Desktop with Nix, and building it as regular Rust program with cargo build instead of tauri build is simpler, but I got this error:

The `tauri` dependency features on the `Cargo.toml` file does not match the allowlist defined under `tauri.conf.json`.
Please run `tauri dev` or `tauri build` or add the `updater` feature.

It was removed in #616

This Nix PR is here if you'd like to have a look: NixOS/nixpkgs#251858

[pascalbreuninger]

Hey @maxbrunet, we'd like to keep the updater feature out of the cargo.toml as it breaks local development if you don't have the correct (sensitive) environment variables. The problem with building it as a standalone rust problem is that you're not going to rebuild the UI