Textarea with summary and counter doesn't respect count only setting

Problem/Motivation

The textarea with summary and counter does not respect the count only setting in the form widget. It seems validation is done no matter what you do. Looking at the code, it's a seemingly small issue to fix.

Steps to reproduce

Install latest version of the module (2.3.0), create a textarea with summary field that uses the textarea with summary and counter form widget. Check the count only setting. Exceed the field character max character count when the count only setting is checked.

Proposed resolution

Make small adjustment in the code in accordance with the other widgets.