server: remove unused code, replace deprecated func

Signed-off-by: Steve Kriss <steve@heptio.com>

pkg/cmd/server/server.go

@@ -30,6 +30,7 @@ import (
 	"time"
 
 	"github.com/pkg/errors"
+	"github.com/prometheus/client_golang/prometheus/promhttp"
 	"github.com/sirupsen/logrus"
 	"github.com/spf13/cobra"
 	"github.com/spf13/pflag"
@@ -67,7 +68,6 @@ import (
 	"github.com/heptio/ark/pkg/util/kube"
 	"github.com/heptio/ark/pkg/util/logging"
 	"github.com/heptio/ark/pkg/util/stringslice"
-	"github.com/prometheus/client_golang/prometheus/promhttp"
 )
 
 const (
@@ -222,7 +222,7 @@ func newServer(namespace, baseName string, config serverConfig, logger *logrus.L
 		arkClient:             arkClient,
 		discoveryClient:       arkClient.Discovery(),
 		dynamicClient:         dynamicClient,
-		sharedInformerFactory: informers.NewFilteredSharedInformerFactory(arkClient, 0, namespace, nil),
+		sharedInformerFactory: informers.NewSharedInformerFactoryWithOptions(arkClient, 0, informers.WithNamespace(namespace)),
 		ctx:            ctx,
 		cancelFunc:     cancelFunc,
 		logger:         logger,
@@ -488,13 +488,6 @@ func getBlockStore(cloudConfig api.CloudProviderConfig, manager plugin.Manager)
 	return blockStore, nil
 }
 
-func durationMin(a, b time.Duration) time.Duration {
-	if a < b {
-		return a
-	}
-	return b
-}
-
 func (s *server) initRestic(providerName string) error {
 	// warn if restic daemonset does not exist
 	if _, err := s.kubeClient.AppsV1().DaemonSets(s.namespace).Get(restic.DaemonSet, metav1.GetOptions{}); apierrors.IsNotFound(err) {