Rover/CustomBuildServer: battery current limiter showing as not-included

[rmackay9]

Bug Report

The custom build server is showing that Rover-4.7.0-beta doesn't include the battery current limiting feature but when I install it using Mission Planner I can see the MOT_BATT_WATT parameter is present. I think the issue is here in extract_features.py.

This is related to this 4.7.0 beta testing discussion

Issue details

Please describe the problem

Version
Rover-4.7.0-beta

Platform
[ ] All
[ ] AntennaTracker
[ ] Copter
[ ] Plane
[x] Rover
[ ] Submarine

Hardware type
CubeOrange

[peterbarker]

It's also a bug in test_build_options.py where we only check the feature is in/out on Plane