Mock microcontroller so we don't use Blinka's board detect.

Author: tannewt

docs/conf.py

@@ -20,7 +20,7 @@
 # Uncomment the below if you use native CircuitPython modules such as
 # digitalio, micropython and busio. List the modules you use. Without it, the
 # autodoc module docs will fail to generate with a warning.
-autodoc_mock_imports = ["board"]
+autodoc_mock_imports = ["board", "microcontroller"]
 autodoc_member_order = "bysource"
 add_module_names = False