Fix finite streams

[divyanshupundir]

Earlier if params|length == 0 was used to check if the stream was a finite (command along with associated progress data) or an infinite (simple data stream eg. position updates) one.

This was correct for most cases except for calibration methods (there could be more). Therefore, the old logic is replaced by a simple is_finite check.

[divyanshupundir]

Thanks for reviewing.