Run gopls modernize on codebase (#34751)

Recent modernize fixes:
https://github.com/golang/tools/commits/master/gopls/internal/analysis/modernize

modules/repository/init.go

@@ -125,7 +125,7 @@ func InitializeLabels(ctx context.Context, id int64, labelTemplate string, isOrg
 	}
 
 	labels := make([]*issues_model.Label, len(list))
-	for i := 0; i < len(list); i++ {
+	for i := range list {
 		labels[i] = &issues_model.Label{
 			Name:           list[i].Name,
 			Exclusive:      list[i].Exclusive,