Welcome to the Bot Framework SDK for .NET repository, which is the home for the libraries and packages that enable developers to build sophisticated bot applications using .NET.
Fixes #4582
## Description
This PR adds the `/.default` suffix to the scope for MSI authentication.
## Specific Changes
- Updated `ManagedIdentityAuthenticator` to add the suffix to the scope.
## Testing
These images show the fix working with a bot deployed in _AKS_ and another one deployed in an _Azure App Service_.
![image](https://github.com/southworks/botbuilder-js/assets/44245136/08e88fae-f003-4de6-8bcd-51d4f0d6812c)
This port is not needed since we couldn't reproduce the issue in BotBuilder-DotNet. Even though the scope doesn't include the '/.default' suffix, the bot authenticates with no errors.
The changes in https://github.com/microsoft/botbuilder-js/pull/4607 may need to be ported to maintain parity with microsoft/botbuilder-js.