我无法从公司代理后面设置 Flutter。当我运行 flutter doctor 时，我得到 407 Proxy Authentication Required。我已正确设置 http_proxy、https_proxy 和 no_proxy。我使用任何其他 CLI 应用都没有问题。
$ flutter doctor
Building flutter tool...
Running pub upgrade...
Proxy failed to establish tunnel (407 Proxy Authentication Required)
Error (69): Unable to 'pub upgrade' flutter tool. Retrying in five seconds... (9 tries left)
我使用的是 Windows。