Use promauto to register stats in bdns (#8480)

This was accidentally deleted along with the idMismatchCounter in #8445.

This is an alternative approach to #8474, and perhaps a reasonable
default pattern for all stats registration in Boulder.

For more on promauto, see its documentation:
https://pkg.go.dev/github.com/prometheus/[email protected]/prometheus/promauto

Author: mcpherrinm

bdns/dns.go

@@ -18,6 +18,7 @@ import (
 	"github.com/jmhodges/clock"
 	"github.com/miekg/dns"
 	"github.com/prometheus/client_golang/prometheus"
+	"github.com/prometheus/client_golang/prometheus/promauto"
 
 	"github.com/letsencrypt/boulder/iana"
 	blog "github.com/letsencrypt/boulder/log"
@@ -92,23 +93,23 @@ func New(
 		userAgent: userAgent,
 	}
 
-	queryTime := prometheus.NewHistogramVec(
+	queryTime := promauto.With(stats).NewHistogramVec(
 		prometheus.HistogramOpts{
 			Name:    "dns_query_time",
 			Help:    "Time taken to perform a DNS query",
 			Buckets: metrics.InternetFacingBuckets,
 		},
 		[]string{"qtype", "result", "resolver"},
 	)
-	totalLookupTime := prometheus.NewHistogramVec(
+	totalLookupTime := promauto.With(stats).NewHistogramVec(
 		prometheus.HistogramOpts{
 			Name:    "dns_total_lookup_time",
 			Help:    "Time taken to perform a DNS lookup, including all retried queries",
 			Buckets: metrics.InternetFacingBuckets,
 		},
 		[]string{"qtype", "result", "retries", "resolver"},
 	)
-	timeoutCounter := prometheus.NewCounterVec(
+	timeoutCounter := promauto.With(stats).NewCounterVec(
 		prometheus.CounterOpts{
 			Name: "dns_timeout",
 			Help: "Counter of various types of DNS query timeouts",