Inheritance: Akka.Remote.TestKit.MultiNodeConfig
 protected DistributedPubSubMediatorSpec(DistributedPubSubMediatorSpecConfig config) : base(config)
 {
     _first = config.First;
     _second = config.Second;
     _third = config.Third;
 }
 protected DistributedPubSubMediatorSpec(DistributedPubSubMediatorSpecConfig config) : base(config, typeof(DistributedPubSubMediatorSpec))
 {
     _first  = config.First;
     _second = config.Second;
     _third  = config.Third;
 }