@Override
	public String notFound() {
		return "notFound fallback";
	}
When the service is blown, the fallback operation is performed.

@author fangjian0423, MieAh
spring-cloud-alibaba-examples/nacos-example/nacos-discovery-example/nacos-discovery-consumer-example/src/main/java/com/alibaba/cloud/examples/feign/EchoClientFallback.java