Acquiring tokens for resources fails with consnet issues

[richardspence]

Basically updating an app to talk to more resources ultimately breaks existing users that are already onboarded to the app. The workaround we have to this is to have users remove the app from their list of consented apps so that upon the next login Azure would ask for consent again.

Repro:

1. Create an app in AAD
2. User "Bob" logins in to app
3. App is updated with perms to talk to another resource (say Graph or service ABC)
4. Acquire delegation token for Graph or ABC
5. It fails due to user consent.

The fix I think would be to capture the consent failure, generate a login url and append context &prompt=consent.