doc: correct cjs code to match mjs code

PR-URL: #39509
Reviewed-By: Tobias Nießen <tniessen@tnie.de>
Reviewed-By: Harshitha K P <harshitha014@gmail.com>
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Luigi Pinca <luigipinca@gmail.com>
Reviewed-By: Vladimir de Turckheim <vlad2t@hotmail.com>

doc/api/async_hooks.md

@@ -374,14 +374,14 @@ net.createServer((conn) => {}).listen(8080);
 
 ```cjs
 const { createHook, executionAsyncId } = require('async_hooks');
-const { fd } = require('process').stdout;
+const { stdout } = require('process');
 const net = require('net');
 
 createHook({
   init(asyncId, type, triggerAsyncId) {
     const eid = executionAsyncId();
     fs.writeSync(
-      fd,
+      stdout.fd,
       `${type}(${asyncId}): trigger: ${triggerAsyncId} execution: ${eid}\n`);
   }
 }).enable();