Look into griffe API documentation warnings

[JaroCamphuijsen]

When building the documentation (locally), we get a lot of WARNINGs from griffe, the API documentation builder. It would be nice to get rid of these warnings, either by improving the docstrings with the suggested changes, or by turning them off if we don't approve.

e.g. (the warnings come in pairs like this)

WARNING -  griffe: mibitrans/visualize/plot_surface.py:24: No type or annotation for
           parameter '**kwargs '
WARNING -  griffe: mibitrans/visualize/plot_surface.py:24: Parameter '**kwargs ' does not
           appear in the function signature