*: replace 'grpc.ErrClientConnTimeout' with 'context.DeadlineExceeded'

Signed-off-by: Gyu-Ho Lee <gyuhox@gmail.com>

integration/v3_grpc_test.go

@@ -1372,7 +1372,7 @@ func TestTLSGRPCRejectInsecureClient(t *testing.T) {
 	// nil out TLS field so client will use an insecure connection
 	clus.Members[0].ClientTLSInfo = nil
 	client, err := NewClientV3(clus.Members[0])
-	if err != nil && err != grpc.ErrClientConnTimeout {
+	if err != nil && err != context.DeadlineExceeded {
 		t.Fatalf("unexpected error (%v)", err)
 	} else if client == nil {
 		// Ideally, no client would be returned. However, grpc will
@@ -1408,7 +1408,7 @@ func TestTLSGRPCRejectSecureClient(t *testing.T) {
 	client, err := NewClientV3(clus.Members[0])
 	if client != nil || err == nil {
 		t.Fatalf("expected no client")
-	} else if err != grpc.ErrClientConnTimeout {
+	} else if err != context.DeadlineExceeded {
 		t.Fatalf("unexpected error (%v)", err)
 	}
 }
@@ -1565,8 +1565,8 @@ func testTLSReload(t *testing.T, cloneFunc func() transport.TLSInfo, replaceFunc
 	// 5. expect dial time-out when loading expired certs
 	select {
 	case gerr := <-errc:
-		if gerr != grpc.ErrClientConnTimeout {
-			t.Fatalf("expected %v, got %v", grpc.ErrClientConnTimeout, gerr)
+		if gerr != context.DeadlineExceeded {
+			t.Fatalf("expected %v, got %v", context.DeadlineExceeded, gerr)
 		}
 	case <-time.After(5 * time.Second):
 		t.Fatal("failed to receive dial timeout error")