docs cleanup

docs/source/SKABaseDevice.rst

docs/source/State_Machine.rst

src/ska/base/base_device.py

src/ska/base/commands.py

src/ska/base/logger_device.py

src/ska/base/master_device.py

src/ska/base/obs_device.py

src/ska/base/state_machine.py

src/ska/base/subarray_device.py

tests/conftest.py

tests/test_base_device.py