add title to api.rst and add other modules to mock docs imports

Author: FoamyGuy

docs/api.rst

@@ -4,5 +4,8 @@
 .. If your library file(s) are nested in a directory (e.g. /adafruit_foo/foo.py)
 .. use this format as the module name: "adafruit_foo.foo"
 
+API Reference
+#############
+
 .. automodule:: adafruit_displayio_sh1106
     :members:

docs/conf.py

@@ -25,7 +25,7 @@
 # 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 = ["displayio", "micropython"]
+autodoc_mock_imports = ["displayio", "micropython", "busdisplay", "fourwire", "i2cdisplaybus"]
 
 
 intersphinx_mapping = {