title: Instance name is displayed as "unknown" on Eureka Dashboard instead of service name
body: <p>I am working on microservices with Spring boot and using eureka as server. I have registered my service on Eureka server but on Eureka Dashboard, service name is displaying as "Unknown "instead of service name which i configured in application.yml.</p>
  
  <p>below are the both yml config
  server:
    port: 8761</p>
  
  <p>spring:
    application:
      name: eureka-server</p>
  
  <p>eureka:
    instance:
      hostname: localhost
    client:
      register-with-eureka: false
      fetch-registry: false
      service-url:
        default-zone: http://${eureka.instance.hostname}:${server.port}/eureka/</p>
  
  <hr>
  
  <p>eureka:
     client:
          serviceUrl:
          defaultZone: <a href="http://localhost:8761/eureka/" rel="nofollow noreferrer">http://localhost:8761/eureka/</a>
      instance:
          appname: reporting-engine
  server:
    port: 0
  instance:
    preferIpAddress: true
  spring:
      application:
            name: reporting-engine</p>
  
  <hr>