test: de-flake test-dns-idna2008.js

* use known well-behaved DNS server
* force pass on ESERVFAIL

PR-URL: https://github.com/nodejs/node/pull/26473
Fixes: https://github.com/nodejs/node/issues/25870


Reviewed-By: Gireesh Punathil <gpunathi@in.ibm.com>
Reviewed-By: Rich Trott <rtrott@gmail.com>
Reviewed-By: Joyee Cheung <joyeec9h3@gmail.com>