code: @Deprecated
    public AtomixClusterBuilder setReachabilityThreshold(int threshold) {
      GroupMembershipProtocolConfig protocolConfig = config.getProtocolConfig();
      if (protocolConfig instanceof HeartbeatMembershipProtocolConfig) {
        ((HeartbeatMembershipProtocolConfig) protocolConfig).setPhiFailureThreshold(threshold);
      }
      return this;
    }
docs: Sets the reachability failure detection threshold.
  <p>
  Reachability of cluster members is determined using a phi-accrual failure detector. The reachability threshold
  is the phi threshold after which a peer will be determined to be unreachable.
  
  @param threshold the reachability failure detection threshold
  @return the cluster builder
  @deprecated since 3.0.2