fix(snix/default.nix): fix comment

Rust docs are deployed to snix.dev/rustdoc, not docs.snix.dev.

Change-Id: I5910457608fa9db05c7ecb5c4b7f3c4260c04b8e
Reviewed-on: https://cl.snix.dev/c/snix/+/30311
Autosubmit: Florian Klink <flokli@flokli.de>
Tested-by: besadii
Reviewed-by: Bence Nemes <nemes.bence1@gmail.com>

snix/default.nix

@@ -62,7 +62,7 @@ in
   # Shell, but with tools necessary to run the integration tests
   shell-integration = (import ./shell.nix { inherit pkgs; withIntegration = true; });
 
-  # Build the Rust documentation for publishing on docs.snix.dev.
+  # Build the Rust documentation for publishing on snix.dev/rustdoc.
   rust-docs = pkgs.stdenv.mkDerivation {
     inherit cargoDeps src;
     name = "snix-rust-docs";