Logging with google-cloud-logging-logback on K8S: resources.labels are empty #2912

I'm trying the used structured logging with google-cloud-logging-logback on Kubernetes.
Most of the resource labels are empty, except project_id and zone:

 resource: {
  labels: {
   cluster_name: ""    
   container_name: ""    
   instance_id: ""    
   namespace_id: ""    
   pod_id: ""    
   project_id: "<project ID>"    
   zone: "<zone>"    
  }
  type: "container"   
 }

I guess the reason for this is that only project_id and zone are configured for resource of type container:

https://github.com/GoogleCloudPlatform/google-cloud-java/blob/937e49d7159c9327255e167f6339c51bb7372c37/google-cloud-logging/src/main/java/com/google/cloud/logging/MonitoredResourceUtil.java#L95