Fix: register ManagedFieldsEntry and FieldsV1 classes into kryo

Change-Id: I4a9f747b9b3d91a75f5f90805daf34a13726e7e0
(cherry picked from commit 7388ff5dfb98a69cba2deaf3cb29d0178072ced5)
diff --git a/apps/k8s-networking/app/src/main/java/org/onosproject/k8snetworking/impl/DistributedK8sEndpointsStore.java b/apps/k8s-networking/app/src/main/java/org/onosproject/k8snetworking/impl/DistributedK8sEndpointsStore.java
index 3bb88e4..d0524a0 100644
--- a/apps/k8s-networking/app/src/main/java/org/onosproject/k8snetworking/impl/DistributedK8sEndpointsStore.java
+++ b/apps/k8s-networking/app/src/main/java/org/onosproject/k8snetworking/impl/DistributedK8sEndpointsStore.java
@@ -20,6 +20,8 @@
 import io.fabric8.kubernetes.api.model.EndpointPort;
 import io.fabric8.kubernetes.api.model.EndpointSubset;
 import io.fabric8.kubernetes.api.model.Endpoints;
+import io.fabric8.kubernetes.api.model.FieldsV1;
+import io.fabric8.kubernetes.api.model.ManagedFieldsEntry;
 import io.fabric8.kubernetes.api.model.ObjectMeta;
 import io.fabric8.kubernetes.api.model.ObjectReference;
 import org.onlab.util.KryoNamespace;
@@ -79,6 +81,8 @@
             .register(EndpointAddress.class)
             .register(ObjectReference.class)
             .register(EndpointPort.class)
+            .register(ManagedFieldsEntry.class)
+            .register(FieldsV1.class)
             .register(LinkedHashMap.class)
             .register(Collection.class)
             .build();