// 使用默认php版本: 
composer update
// php7.4全路径：
/usr/local/php7.4/bin/php /usr/local/bin/composer7 update

// 使用默认php版本: 
composer install 
// php7.4全路径： 
/usr/local/php7.4/bin/php /usr/local/bin/composer7 install

composer config -g repo.packagist composer https://mirrors.cloud.tencent.com/composer/