final List<DnsQueryListener> dnsQueryListeners() {
        return dnsQueryListeners;
    }
Adds the {@link DnsQueryListener} that listens to the result of {@link DnsRecord} queries.
If no {@link DnsQueryListener} is configured, {@link DnsQueryListener#of()} is used by default.
core/src/main/java/com/linecorp/armeria/client/endpoint/dns/DnsEndpointGroupBuilder.java