`flexmeasures show beliefs` duplicated sensor names

[victorgarcia98]

The command flexmeasures show beliefs can be used to save the data from beliefs as CSV. It takes a sensor or list of sensors as part of its input and, in case of encountering sensors with duplicated names, it adds the sensor ID.

Nonetheless, it would be nicer if it included the asset name. It could be even be extended to show part or the complete FM entity path (e.g. Account > Asset 1 > Asset 2 > ... > Asset N > Sensor).