// If set, the name of the container from PodSpec that this ephemeral container targets.
  // The ephemeral container will be run in the namespaces (IPC, PID, etc) of this container.
  // If not set then the ephemeral container uses the namespaces configured in the Pod spec.
  //
  // The container runtime must implement support for this feature. If the runtime does not
  // support namespace targeting then the result of setting this field is undefined.