3461. [bug] Negative responses could incorrectly have AD=1

set. [RT #32237]

bin/tests/system/dnssec/clean.sh

@@ -63,6 +63,7 @@ rm -f ns3/ttlpatch.example.db.patched
 rm -f ns3/split-smart.example.db
 rm -f ns3/inline.example.db.signed
 rm -f ns3/lower.example.db ns3/upper.example.db ns3/upper.example.db.lower
+rm -f ns6/optout-tld.db
 rm -f nosign.before
 rm -f signing.out*
 rm -f canonical?.*