Remove method documentation from most class docs (e.g. geoms)

[machow]

quartodoc by default embeds method documentation for classes (e.g. geom_abline).

However, plotnine has this disabled using the numpydoc option numpydoc_show_class_members.

We can disable this manually on each class. Let's add a global option to quartodoc to disable by default (similar to the global dynamic option). Let's wait to get most of the other pieces in first.

[machow]

addressed by https://github.com/machow/plotnine-docs-demo/pull/17