dns: make dns.promises enumerable

PR-URL: #26592
Reviewed-By: Anna Henningsen <anna@addaleax.net>
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Matteo Collina <matteo.collina@gmail.com>
Reviewed-By: Michaël Zasso <targos@protonmail.com>

Author: cjihrig

lib/dns.js

@@ -313,7 +313,7 @@ bindDefaultResolver(module.exports, getDefaultResolver());
 Object.defineProperties(module.exports, {
   promises: {
     configurable: true,
-    enumerable: false,
+    enumerable: true,
     get() {
       if (promises === null) {
         promises = require('internal/dns/promises');