Set default value checkbox dissapears and Summary in Default value is set as required.

Problem/Motivation

Steps to reproduce

I create a new text field: Text (formatted, long, with summary).
I toggle Required field, Summary input, Require summary and Set default value.
I save the settings.

After that, if I want to modify the field, I can not save it because it says: "Error message: Summary field is required". And the Summary field in Default value has a star next to it.
Also the Default value toggle box dissapeared, only the input box appears.

To correct the issue, I have to enter any text on the Default value:Summary field and save. Then, when I edit the field again, the Set default value appears again and I can toggle off the boxes.

Proposed resolution

The Summary field in the Default value input box should not be required in any case.

Remaining tasks

User interface changes

Introduced terminology

API changes

Data model changes

Release notes snippet