build-profile: also accept nvidia license

There seems to be recursive dependencies between adding video drivers and checking if the unfree flag is set.

tests/build-profile.nix

@@ -14,6 +14,7 @@ let
     nixpkgs.config = {
       allowBroken = true;
       allowUnfree = true;
+      nvidia.acceptLicense = true;
     };
   };
 in (import <nixpkgs/nixos> {