services.statsd: add simple test

pkgs/development/node-packages/default-v6.nix

@@ -68,8 +68,4 @@ nodePackages // {
     '';
     buildInputs = oldAttrs.buildInputs ++ [ pkgs.phantomjs2 ];
   });
-
-  # create an alias to ensure that Nix finds the appropriate package
-  # by adopting the naming convention (statsd-`type`-backend) for statsd plugins.
-  statsd-stackdriver-backend = nodePackages.stackdriver-statsd-backend;
 }