[later phase] Support props defaults that have config dependencies

Here's a patch that updates the existing test coverage to use the text field type instead of the string field type and it does not cause a test failure. That proves that Component::calculateDependencies() is missing some additional logic.

As the issue summary says: Look at how Drupal's existing Field UI handles this.

FYI: I marked this for a later phase because this is IMHO low-risk. It's a known TODO, with a known solution, in Drupal core.

Sibling follow-up issue 📌 [PP-1] Default props values should support files/images Postponed is much riskier, so is not marked for a later phase.

✨ Allow specifying default props values when opting an SDC in for XB Fixed is in.

Wim Leers → credited catch → .