chore(lint): modernize Go (#7536)

Use modern Go constructs through the modernize analyzer from the
golang.org/x/tools package.

Signed-off-by: Ville Vesilehto <ville@vesilehto.fi>

plugin/dnssec/cache.go

@@ -32,7 +32,7 @@ func periodicClean(c *cache.Cache, stop <-chan struct{}) {
 			// we sign for 8 days, check if a signature in the cache reached 75% of that (i.e. 6), if found delete
 			// the signature
 			is75 := time.Now().UTC().Add(twoDays)
-			c.Walk(func(items map[uint64]interface{}, key uint64) bool {
+			c.Walk(func(items map[uint64]any, key uint64) bool {
 				for _, rr := range items[key].([]dns.RR) {
 					if !rr.(*dns.RRSIG).ValidityPeriod(is75) {
 						delete(items, key)

plugin/dnssec/dnssec.go

@@ -118,7 +118,7 @@ func (d Dnssec) sign(rrs []dns.RR, signerName string, ttl, incep, expir uint32,
 		return sgs, nil
 	}
 
-	sigs, err := d.inflight.Do(k, func() (interface{}, error) {
+	sigs, err := d.inflight.Do(k, func() (any, error) {
 		var sigs []dns.RR
 		for _, k := range d.keys {
 			if d.splitkeys {

plugin/dnssec/setup.go

@@ -3,6 +3,7 @@ package dnssec
 import (
 	"fmt"
 	"path/filepath"
+	"slices"
 	"strconv"
 	"strings"
 
@@ -94,13 +95,7 @@ func dnssecParse(c *caddy.Controller) ([]string, []*DNSKEY, int, bool, error) {
 	// Check if each keys owner name can actually sign the zones we want them to sign.
 	for _, k := range keys {
 		kname := plugin.Name(k.K.Header().Name)
-		ok := false
-		for i := range zones {
-			if kname.Matches(zones[i]) {
-				ok = true
-				break
-			}
-		}
+		ok := slices.ContainsFunc(zones, kname.Matches)
 		if !ok {
 			return zones, keys, capacity, splitkeys, fmt.Errorf("key %s (keyid: %d) can not sign any of the zones", string(kname), k.tag)
 		}