private void closeResources() {
        Utils.closeQuietly(member::stop, "worker group member");
        Utils.closeQuietly(herderMetrics::close, "herder metrics");
        this.uponShutdown.forEach(closeable -> Utils.closeQuietly(closeable, closeable != null ? closeable.toString() : "<unknown>"));
    }
Close resources managed by this herder but which are not explicitly started.
connect/runtime/src/main/java/org/apache/kafka/connect/runtime/distributed/DistributedHerder.java