fix rerun the completed vmiMigration

Signed-off-by: clyi <clyi@alauda.io>

Author: changluyi

pkg/controller/kubevirt.go

@@ -65,6 +65,11 @@ func (c *Controller) handleAddOrUpdateVMIMigration(key string) error {
 		return nil
 	}
 
+	if vmiMigration.Status.MigrationState.Completed {
+		klog.Infof("VirtualMachineInstanceMigration %s migration state is completed, skipping", key)
+		return nil
+	}
+
 	vmi, err := c.config.KubevirtClient.VirtualMachineInstance(namespace).Get(context.TODO(), vmiMigration.Spec.VMIName, metav1.GetOptions{})
 	if err != nil {
 		utilruntime.HandleError(fmt.Errorf("failed to get VMI by name %s: %w", vmiMigration.Spec.VMIName, err))