`WaitableLoRaRequest` properties `ProcessingSucceeded`, `ProcessingFailed` and `ProcessingFailedReason` can be out of sync

[bastbu]

Expected Behavior

On a WaitableLoRaRequest we ProcessingSucceeded should always be false if ProcessingFailed is true, and/or if a ProcessingFailedReason is present.

Current Behavior

ProcessingFailed and ProcessingSucceeded are set separately in NotifySucceeded and NotifyFailed respectively. Depending on which property one uses for assertions in tests, one might get ambiguous responses based on which property one queries. Also, we should consider whether we want to have a LoRaDeviceRequestFailedReason.None to indicate that no error happened (otherwise we have states where ProcessingSucceeded is true and LoRaDeviceRequestFailedReason is ApplicationError).

[roel4ez]

we should look at this, and exclude the fact that the callback could happen twice.