Fix golangci-lint failures with v2.11.3

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

Author: oschwald

main.go

@@ -15,7 +15,7 @@ import (
 	"fmt"
 	"log"
 	"os"
-	"sort" //nolint:depguard // preexisting
+	"slices"
 	"strings"
 
 	"github.com/maxmind/mm-geofeed-verifier/v4/verify"
@@ -55,7 +55,7 @@ func run() error {
 	)
 	if err != nil {
 		if errors.Is(err, verify.ErrInvalidGeofeed) {
-			log.Printf( //nolint:gosec // logging verified geofeed data
+			log.Printf(
 				"Found %d invalid rows out of %d rows in total, examples by type:",
 				c.Invalid,
 				c.Total,
@@ -79,10 +79,17 @@ func run() error {
 	for asNumber := range asnCounts {
 		asNumbers = append(asNumbers, asNumber)
 	}
-	sort.Slice(
+	slices.SortFunc(
 		asNumbers,
-		func(i, j int) bool {
-			return asnCounts[asNumbers[i]] > asnCounts[asNumbers[j]]
+		func(a, b uint) int {
+			switch {
+			case asnCounts[a] > asnCounts[b]:
+				return -1
+			case asnCounts[a] < asnCounts[b]:
+				return 1
+			default:
+				return 0
+			}
 		},
 	)
 	for _, asNumber := range asNumbers {