gem-control finite 3 phase environments.

[bhk11]

Currently is src/gem-controllers/stages/disc_output_stage.py the return for to_6b_discrete() not implemented and raises an error.
The old implementation return np.sum([a * 2 ** n for n, a in enumerate(multi_discrete_action[::-1])]) does not work as expected.

[bhk11]

Further information, the controller only applies action 0 with the old return of the function.
Thus, the controller don't follow the reference and the transient response due to the induced voltage is visible in the currents.