Respect NO_PROXY environment variable / configuration

[u1735067]

Feature description

Hello,

same report as in microsoft/Git-Credential-Manager-for-Windows#876, it appear there's no NO_PROXY support in GCMC (whatever the source is): https://github.com/microsoft/Git-Credential-Manager-Core/blob/v2.0.318-beta/src/shared/Microsoft.Git.CredentialManager/Settings.cs#L341

So git is properly handling requests, but GCMC can leaks informations through the proxy while it shouldn't.

Could GCMC handle this environment variable the same way gitdoes, which is https://curl.haxx.se/docs/manual.html (§Environment Variables, as per https://github.com/git/git/search?q=no_proxy&unscoped_q=no_proxy)?

Best,