[FEATURE] Unit tests for the I2C bus

[RichardBrown384]

Is your feature request related to a problem? Please describe.
The I2C bus isn't tested (hence all the log statements in the code).

Describe the solution you'd like
The I2C bus should test the following

• Normal expected operations (START/STOP + Transmit And Receive)
• The behaviour when something unexpected happens (STOP during receive for example).

Describe alternatives you've considered
None.

Additional context
None.