Add option to hide "Formatting options" dropdown

Problem/Motivation

Since there is now an option to disable markdown formatting in the table field, displaying the "Formatting options" dropdown with the field widget can be confusing to users when the formatting does not show.

It would be great if there was an option to hide the formatting dropdown in the field widget settings. I think this should be in the field widget settings since the markdown formatting option can be disabled per-instance in the formatter options.