Anonymous Authentication Support

[tecton]

Is your feature request related to a problem? Please describe.
I'm trying to use Teams App Test Tool for local debugging. It simulates msteams channel and doesn't require authentication.
Bot framework can disable security by setting "MicrosoftAppId" and "MicrosoftAppPassword“ an empty string. (link)
But when using Agents SDK, it seems that I have to specify "ClientId" and "ClientSecret" in client secret auth type. Otherwise the RestChannelServiceClientFactory would have error.

Describe the solution you'd like
It would be convenient if Agents SDK has a new class that implements IChannelServiceClientFactory and supports anonymous authentication.

Describe alternatives you've considered
If "ClientId" and "ClientSecret" are empty string, rest channel service client could ignore the authentication.

Additional context

[tracyboehrer]

@tecton This is a work in progress. Teams Toolkit has some expectations about this setup and the settings you mention don't exist anymore (in the same way). With that said... I completely agree that the local debugging story needs to evolve prior to GA of Agents SDK.