不小心把自己原先的項目里的pom文件給覆蓋了。於是重構，但出現如下錯誤：
Project build error: Non-resolvable parent POM for com.kaspar:siyunlian-master:0.0.1-SNAPSHOT: Failure to find org.springframework.boot:spring-boot-starter-parent:pom:2.2.6.RELEASE in http:// maven.aliyun.com/nexus/content/repositories/central/ was cached in the local repository, resolution will not be reattempted until the update interval of alimaven has elapsed or updates are forced and 'parent.relativePath' points at no local POM
修改版本號錯誤消失。
然后重新update 項目。錯誤解決。