Motivation:
When following a CNAME it is possible there are multiple name servers to query against. However DnsNameResolverContext#followCname explicitly only uses the first name server address when attempting the query. This may lead to resolution failures because we didn't try all the available name servers.
Modifications:
DnsNameResolverContext#followCname should not just try the first name server, but it should try all name servers
Result:
More complete CNAME resolution.