Update docs.amdc.dev current sensor calibration article to discuss amds_convert_voltage

[elsevers]

Abstract

Context

We have recently added new code to the AMDC-Firmware repo to help with interpreting AMDS measurements. See this PR:

• Fix AMDS data error AMDC-Firmware#449

The Use of Calibration Data section of our Current Sensor Calibration article is essentially implementing this same functionality.

Approach

Close this issue via a PR that adds a short couple of sentences to the end of the Use of Calibration Data section that explain how the amds_convert_voltage() can be used for this functionality.