dns: remove dns.promises experimental warning

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>
Signed-off-by: Beth Griggs <Bethany.Griggs@uk.ibm.com>

Author: cjihrig

lib/dns.js

@@ -321,8 +321,6 @@ Object.defineProperties(module.exports, {
       if (promises === null) {
         promises = require('internal/dns/promises');
         promises.setServers = defaultResolverSetServers;
-        process.emitWarning('The dns.promises API is experimental',
-                            'ExperimentalWarning');
       }
       return promises;
     }

test/parallel/test-dns-lookup.js

@@ -27,8 +27,6 @@ common.expectWarning({
   'internal/test/binding': [
     'These APIs are for internal testing only. Do not use them.'
   ],
-  // For dns.promises.
-  'ExperimentalWarning': 'The dns.promises API is experimental',
   // For calling `dns.lookup` with falsy `hostname`.
   'DeprecationWarning': {
     DEP0118: 'The provided hostname "false" is not a valid ' +