code: public ZooKeeperUpdatingListenerBuilder connectTimeout(Duration connectTimeout) {
          requireNonNull(connectTimeout, "connectTimeout");
          checkArgument(!connectTimeout.isZero() && !connectTimeout.isNegative(),
                        "connectTimeout: %s (expected: > 0)", connectTimeout);
          return connectTimeoutMillis(connectTimeout.toMillis());
      }
docs: Sets the connect timeout.
  
  @param connectTimeout the connect timeout
  
  @throws IllegalStateException if this builder is constructed with
  {@link #ZooKeeperUpdatingListenerBuilder(CuratorFramework, String)}