[REF]: remove nix package definition

Author: sijanthapa171

modules/core/system.nix

@@ -68,7 +68,6 @@ in
       keep-derivations = true;
     };
     optimise.automatic = true;
-    package = pkgs.nixVersions.latest;
   };
   time.timeZone = "${timezone}";
   i18n.defaultLocale = "${locale}";