解决SpringBoot测试提示Failed to resolve org.junit.platform:junit-platform-launcher:1.5.2
解决方案：只需要添加:junit-platform-launcher依赖即可

  <dependency><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter-test</artifactId><scope>test</scope><exclusions><exclusion><groupId>org.junit.vintage</groupId><artifactId>junit-vintage-engine</artifactId></exclusion></exclusions></dependency><dependency><groupId>org.junit.platform</groupId><artifactId>junit-platform-launcher</artifactId><scope>test</scope></dependency>