Fix the default value on settings form

Problem/Motivation

When opening the form with the settings the "default" value wasn't being filled. For example, create a "ebt_bb" with option "open link in a new tab". Save that and edit the same block again. Is open to see that this field isn't checked.

Steps to reproduce

The field is being saved but the "default" value is trying to retrieve wrongly, without the "link_options" array in the key

Proposed resolution

Update the array key to include the "link_options" there

Remaining tasks

User interface changes

API changes

Data model changes