springboot bootstrap.yml nacos配置中心问题

    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.1.5.RELEASE</version>
        <relativePath/> <!-- lookup parent from repository -->
    </parent>

<!--nacos-->
        <dependency>
            <groupId>com.alibaba.cloud</groupId> 
　　　 <artifactId>spring-cloud-starter-alibaba-nacos-config</artifactId> 
　　　<version>0.2.1.RELEASE</version> 
　　　</dependency>

spring:
  application:
    name: gabriel
  cloud:
    nacos:
      config:
        server-addr: 127.0.0.1:8848
        file-extension: yaml

<dependency>
    <groupId>org.springframework.cloud</groupId>
    <artifactId>spring-cloud-starter-alibaba-nacos-config</artifactId>
    <version>0.2.0.RELEASE</version>
</dependency>  

@RestController
@RequestMapping(value = "/test")
@RefreshScope
public class TestController {

    @Value(value = "${service.name:}")
    private String serverName;

    /**
     *
     * @return
     */
    @RequestMapping(value = "/get_nacos")
    public String getNacos(){
        System.out.println(serverName);
        return serverName;
    }
}