public GracefulShutdownBuilder timeoutMillis(long timeoutMillis) {
        return timeout(Duration.ofMillis(timeoutMillis));
    }
Sets the amount of time to wait before shutting down the server regardless of active requests.
This should be set to a time greater than {@code quietPeriod} to ensure the server shuts down even
if there is a stuck request.

<p>The default is {@link Duration#ZERO}.
core/src/main/java/com/linecorp/armeria/server/GracefulShutdownBuilder.java