wget: fix build on sandboxed Darwin

The tests depend on local network access:
https://gist.github.com/al3xtjames/3b16d74fa83094d34764ceca36f9ebec

Author: al3xtjames

pkgs/tools/networking/wget/default.nix

@@ -40,6 +40,7 @@ stdenv.mkDerivation rec {
     "--without-included-regex"
   ];
 
+  __darwinAllowLocalNetworking = true;
   doCheck = true;
   preCheck = ''
     patchShebangs tests fuzz