async_hooks,test: only use IPv6 in http test

If IPv6 is not supported on a machine, the IPv6 handle will first be
created, this will then fail and default to an IPv4 handle. This causes
the graph to change, as there now is an extra handle.

Backport-PR-URL: #18474
PR-URL: #18143
Fixes: #18003
Reviewed-By: Anna Henningsen <anna@addaleax.net>
Reviewed-By: Rich Trott <rtrott@gmail.com>
Reviewed-By: Anatoli Papirovski <apapirovski@mac.com>
Reviewed-By: James M Snell <jasnell@gmail.com>

test/async-hooks/test-graph.http.js

@@ -1,6 +1,9 @@
 'use strict';
 
 const common = require('../common');
+if (!common.hasIPv6)
+  common.skip('IPv6 support required');
+
 const initHooks = require('./init-hooks');
 const verifyGraph = require('./verify-graph');
 const http = require('http');
@@ -13,7 +16,11 @@ const server = http.createServer(common.mustCall(function(req, res) {
   this.close(common.mustCall());
 }));
 server.listen(0, common.mustCall(function() {
-  http.get(`http://127.0.0.1:${server.address().port}`, common.mustCall());
+  http.get({
+    host: '::1',
+    family: 6,
+    port: server.address().port
+  }, common.mustCall());
 }));
 
 process.on('exit', function() {