Firmware_and_Hardware_Revisions.md moving to Learn

[MoffKalast]

I'm not sure if you want to have the Firmware_and_Hardware_Revisions specifically here in the motor repo to keep it more easily up to date, but I think it would make sense to move it to the new learn wiki.

[MoffKalast]

Note: The pages are now live, so the actual page that should be edited is this one: https://learn.ubiquityrobotics.com/noetic_magnisilver_mcb_revisions

There is the slight issue that we have a kinetic/noetic split for this page which makes it harder to maintain for no reason, so it might make sense to move it to a rosdistro agnostic page, given that it's hidden from nav and it won't affect anything.

[MoffKalast]

Okay I just went ahead and moved it, the definitive new file is now at: https://github.com/UbiquityRobotics/learn/blob/master/unlisted_pages/magnisilver_mcb_revisions.md

And can be found on the wiki at: https://learn.ubiquityrobotics.com/magnisilver_mcb_revisions

Only that one file needs to be edited, and will appear in both noetic and kinetic views.