update kube and vendor dependencies

With kubernetes 1.18 release of client-go, signatures on methods in
generated clientsets, dynamic, metadata, and scale clients have been
modified to accept context.Context as a first argument.
Signatures of Create, Update, and Patch methods have been updated
to accept CreateOptions, UpdateOptions and PatchOptions respectively.
Signatures of Delete and DeleteCollection methods now accept
DeleteOptions by value instead of by reference.
These changes are now accommodated with this PR and client-go
and dependencies are updated to v1.18.0

Signed-off-by: Humble Chirammal <hchiramm@redhat.com>

pkg/utils/util.go

@@ -17,11 +17,11 @@ limitations under the License.
 package utils
 
 import (
+	"context"
 	"fmt"
-	"strings"
-
 	"os"
 	"strconv"
+	"strings"
 	"time"
 
 	crdv1 "github.com/kubernetes-csi/external-snapshotter/v2/pkg/apis/volumesnapshot/v1beta1"
@@ -318,7 +318,7 @@ func GetCredentials(k8s kubernetes.Interface, ref *v1.SecretReference) (map[stri
 		return nil, nil
 	}
 
-	secret, err := k8s.CoreV1().Secrets(ref.Namespace).Get(ref.Name, metav1.GetOptions{})
+	secret, err := k8s.CoreV1().Secrets(ref.Namespace).Get(context.TODO(), ref.Name, metav1.GetOptions{})
 	if err != nil {
 		return nil, fmt.Errorf("error getting secret %s in namespace %s: %v", ref.Name, ref.Namespace, err)
 	}