Should `generate_matrix()` handle `logical` and `character` types?

[lazappi]

Currently, generate_matrix() only works for numeric types but it is also possible to have logical and character matrices. These could be better matches for Python types like string_array for which we currently generate data frames.

[lazappi]

Looking at it more closely, it seems like what we have does match dummy_anndata. It might still be worth adding these at some point but we probably want to sync the changes.