Stimulator battery level not showing in the `CalibrationScene` GUI

[kuff]

Screenshot for reference:

This is caused by the port to Ardity, where some logic has not been updated to how the connection is now being handled. This should be a simple fix.

[kuff]

A version of the ConnectDevice script from before the Ardity port is available here. This is the script responsible for defining the battery level, especially lines 124, 125, and 135 are of interest in this regard.

[kuff]

Fixed as of https://github.com/med-material/vrtactility/commit/478cb420940d0c978800e99e6a18bfbc61acf587.