[Rspamd] Revert custom DNS timeouts

data/conf/rspamd/local.d/options.inc

@@ -2,9 +2,4 @@ dns {
   enable_dnssec = true;
 }
 map_watch_interval = 30s;
-dns {
-  timeout = 6s;
-  retransmits = 4;
-  sockets = 16;
-}
 disable_monitoring = true;