test building in ci with hello-unfree

related to #4

Author: Lillecarl

kubenix/ci/default.nix

@@ -98,7 +98,7 @@ in
                         };
                         pkgs = import nixpkgs { };
                       in
-                      pkgs.hello
+                      pkgs.hello-unfree # test that building works
                     '';
                 };
               };