@Test
    void gracefulShutdownBlockingTaskExecutor() {
        final ScheduledExecutorService executor = Executors.newSingleThreadScheduledExecutor();

        final Server server = Server.builder()
                                    .blockingTaskExecutor(executor, true)
                                    .service("/", (ctx, req) -> HttpResponse.of(200))
                                    .build();

        server.start().join();

        executor.execute(() -> {
            try {
                Thread.sleep(processDelayMillis * 2);
            } catch (InterruptedException ignored) {
                // Ignored
            }
        });

        server.stop().join();

        assertThat(server.config().blockingTaskExecutor().isShutdown()).isTrue();
        assertThat(server.config().blockingTaskExecutor().isTerminated()).isTrue();
    }
Ensure that the connection is not broken even if {@link Service#serve(ServiceRequestContext, Request)}
raises an exception.
core/src/test/java/com/linecorp/armeria/server/ServerTest.java