Set AD bit in the header of DNS queries (#3068)
Set AD bit in the header of DNS queries (#3068)

Fixes broken DNSSEC metrics, lack of this bit being set in queries had no security implications.

jfrazelle/boulder,bmw/boulder,lucasallan/boulder,jcjones/boulder,jsha/boulder,jsha/boulder,bmw/boulder,ibukanov/boulder,jcjones/boulder,ibukanov/boulder,ibukanov/boulder,jsha/boulder,bmw/boulder,lucasallan/boulder,jcjones/boulder,letsencrypt/boulder,jfrazelle/boulder,letsencrypt/boulder,letsencrypt/boulder,jfrazelle/boulder,jfrazelle/boulder,lucasallan/boulder,jcjones/boulder