DeviceCheck macOS 11.1 to 11.3 API Differences

DCAppAttestService.h

Added DCAppAttestService

Added DCAppAttestService.sharedService

Added DCAppAttestService.supported

Added -[DCAppAttestService generateKeyWithCompletionHandler:]

Added -[DCAppAttestService attestKey:clientDataHash:completionHandler:]

Added -[DCAppAttestService generateAssertion:clientDataHash:completionHandler:]