Rodar projeto listavip ConvidadoController

Não estou conseguindo rodar a Controller Convidado, o não mostra nenhuma mensagem e a tela fica branca.

porn.xml

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0"
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>

    <groupId>br.com.alura.listavip</groupId>
    <artifactId>listavip</artifactId>
    <version>1.0-SNAPSHOT</version>

    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
            <version>1.4.1.RELEASE</version>
        </dependency>
        <dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-thymeleaf</artifactId>
    <version>1.4.1.RELEASE</version>
</dependency>
    </dependencies>

</project>

ConvidadoController.java
@Controller
public class ConvidadoController {
      @RequestMapping("/")
        public String index(){
            return "index";
      }