Tabular roles report doesn't show members for Azure AS

[furmangg]

Reverse engineering the Visual Studio project from Azure Analysis Services and running the roles report shows no members.

[furmangg]

Made a little progress on this. AAD users show up in the ExternalMembers collection so the roles report wasn't looping through that collection to populate the report.

There's still more work to do in terms of looking up that user in AAD and expanding the members of groups.

[boulavogue]

The ExternalMembers collection seems to be a standard when adding AAD accounts to Tabular Models