use codeql from unstable

packages.nix

@@ -2,21 +2,12 @@
 
 let
   unstable = import <unstable> {};
+  unstable-nonfree = import <unstable> { config.allowUnfree = true; };
   emacsWithImagemagick = (unstable.emacs.override {
     srcRepo = true;
     imagemagick = unstable.imagemagickBig;
   });
-  nixpkgs-tars = "https://github.com/NixOS/nixpkgs/archive/";
 in {
-  nixpkgs.config = {
-    allowUnfree = true;
-    packageOverrides = pkgs: {
-      pr75524 = import (fetchTarball "${nixpkgs-tars}f7d7980f82cabbf72ddfe07a2bc4996432b44814.tar.gz") {
-        config = config.nixpkgs.config;
-      };
-    };
-  };
-
   programs.zsh.enable = true;
   programs.browserpass.enable = true;
   programs.adb.enable = true;
@@ -41,7 +32,7 @@ in {
   services.tor.client.enable = true;
 
   environment.systemPackages = with pkgs; [
-    pr75524.codeql
+    unstable-nonfree.codeql
 
     # nix
     patchelfUnstable nix-index