fix: AzureApp RoleClaimType with IdentityProvider

[mr-sven]

Adding option to set the default RoleClaimType via AppServicesAuthenticationOptions to use correct roles claim with Microsoft Identity Provider. Fixes #1983

Can be set via

builder.Services.Configure<AppServicesAuthenticationOptions>(AppServicesAuthenticationDefaults.AuthenticationScheme, options =>
{
    options.RoleClaimType = "roles";
});

[mr-sven]

@microsoft-github-policy-service agree

[jmprieur]

LGTM
Thanks @mr-sven

[nis-spiir]

Would love to see this merged.

This should be the default when using AAD as IDP.
Seems to cause a lot of confusion (especially because none of the Microsoft Docs tells you that Role claim is mapped incorrectly, so much for "Easy" Auth 😛)

[jmprieur]

Thanks @mr-sven for this PR, and for your patience.
I propose to take the fix in a simplified way, as, given Easy Auth is using AAD v2.0, the claim will always be "roles"
Proposed another PR: #2166