@Override
    public List<ClientAddressSource> clientAddressSources() {
        return clientAddressSources;
    }
Returns the {@link Executor} which will invoke the callbacks of {@link Server#start()},
{@link Server#stop()} and {@link ServerListener}.

<p>Note: Kept non-public since it doesn't seem useful for users.</p>
core/src/main/java/com/linecorp/armeria/server/DefaultServerConfig.java