[FR] Add voltage sensor to "plus" devices

[MaxRink]

Is your feature request related to a problem? Please describe.

Currently the Volate readout isnt supported on newer "plus" devices

Describe the solution you'd like

Add the Voltage as a sensor

Describe alternatives you've considered

dont do it :S

Additional context

Newer shelly plus devices also track voltage:

apidocs: https://shelly-api-docs.shelly.cloud/gen2/Components/FunctionalComponents/Switch

[MaxRink]

Nevermind, im an idiot :D