[FEATURE] Unit tests for the keyboard

[RichardBrown384]

Is your feature request related to a problem? Please describe. The keyboard isn't tested. See #2 and #4

Describe the solution you'd like The keyboard operations to be tested.

• [x] Tests around the reset protocol
• [x] Tests around transmission
• [x] Tests around receiving
• [x] Tests around the enabling and disabling of various scan modes

Describe alternatives you've considered None

Additional context See #2 and #4

[RichardBrown384]

Closed by #26