[Feature] Read aad2 scopes from environment variables

[NickRimmer]

Hi @Huachao, Thank you a lot for your work and such a great plugin. Looks very promising for me to use.

I would like to suggest a very tiny PR with a feature. I found that all AAD settings can be set per environment except scopes. But on AAD, multiple app registrations can have different scopes (e.g. Dev/User.Default, Prod/User.Default, etc.).

It would be awesome if you could approve my PR and add this feature to your extension. I wasn't able to build vsix package from your current master branch, so based it on a commit with tag v0.25.0 and tested it on my local.

Thank you (;