Convert plugin discovery to attributes

Problem/Motivation

Drupal is moving towards attributes for plugin discovery, see https://www.drupal.org/project/drupal/issues/3396165 📌 [meta] Convert all core plugin types to attribute discovery Postponed

Proposed resolution

Convert plugin discovery to attributes

Remaining tasks

1. Write a merge request
2. Review
3. Commit

User interface changes

None

API changes

Extra Field plugins are now preferably declared through attributes

Data model changes

None