配置镜像方法:
阿里云镜像:composer config -g repo.packagist composer https://mirrors.aliyun.com/composer/ 腾讯云镜像:composer config -g repos.packagist composer https://mirrors.cloud.tencent.com/composer/
中国常用composer 镜像:https://learnku.com/composer/wikis/30594