Fix bug in cloudConnector where annotations can be a nil map

Summary: We recently updated cloudConn to add the clusterID to the pod annotations. However, this can be a nil map if the pod has no annotations, and we need to handle that case.

Test Plan: deployed using Skaffold, with a cloudConnector without any preexisting annotations

Reviewers: vihang

Reviewed By: vihang
Signed-off-by: Michelle Nguyen <michellenguyen@pixielabs.ai>

Differential Revision: https://phab.corp.pixielabs.ai/D10459

GitOrigin-RevId: ecdaeeeb9f2a0328751322b09c8c072e04be06c7

src/vizier/services/cloud_connector/bridge/vzinfo.go

@@ -724,6 +724,9 @@ func (v *K8sVizierInfo) UpdateClusterIDAnnotation(id string) error {
 	}
 
 	ccPod := ccPodsList.Items[0]
+	if ccPod.Annotations == nil {
+		ccPod.Annotations = make(map[string]string)
+	}
 	ccPod.Annotations["cluster-id"] = id
 
 	_, err = v.clientset.CoreV1().Pods(v.ns).Update(context.Background(), &ccPod, metav1.UpdateOptions{})