public EurekaUpdatingListenerBuilder instanceId(String instanceId) {
        instanceInfoBuilder.instanceId(instanceId);
        return this;
    }
Sets the ID of this instance. Derived from {@link #hostname(String)},
{@link #appName(String)} and {@link #port(int)}, if not specified.
eureka/src/main/java/com/linecorp/armeria/server/eureka/EurekaUpdatingListenerBuilder.java