composer install requires php ^7.1

composer install 报错：

Problem 1

- Installation request for doctrine/inflector v1.3.0 -> satisfiable by doctrine/inflector[v1.3.0].

- doctrine/inflector v1.3.0 requires php ^7.1 -> your PHP version (7.0.30) does not satisfy that requirement.

看到提示最小 PHP 版本7.1 到底要不要更换PHP 版本呢？如果这个插件不太重要，可以忽略版本检测，如下代码

composer install --ignore-platform-reqs