[FASTAPI] Object ClaimsIdentity can't be used in 'await' expression

[MattB-msft]

When using Agents Playground in Anonymous mode the JWT middleware for fast API throws as its attempting to call a sync method via an Async pattern.

https://github.com/microsoft/Agents-for-python/blob/a54797cbbe267e0ea8c8b6f10b379a8918dc2d4e/libraries/microsoft-agents-hosting-fastapi/microsoft_agents/hosting/fastapi/jwt_authorization_middleware.py#L66C7-L66C65