Expose ID token in IAuthenticationResult

[ShmuelCammebys]

Is your feature request related to a problem? Please describe.
I was unable to find where the ID token is exposed, because in the MSAL iOS SDK, the ID token is exposed as a property in the auth result returned in the callback (code here and here).IAuthenticationResult only exposes an access token (in getAccessToken()), and the ID token can only be accessed through the account (i.e. getAccount().getIdToken()).

Describe the solution you'd like
Having a getter in AuthenticationResult which returned getAccount().getIdToken() would make this more discoverable, because it would have API parity with the iOS SDK.

Describe alternatives you've considered

Additional context