ComponentSourceInterface::submitConfigurationForm and validateConfigurationForm are never called

This AFAIK ties into follow-ups opened for 📌 Add support for Blocks as Components Active that were never followed up on. A quick scan suggests:

• 📌 Define how block settings should be presented in the UI Active
• 📌 [PP-1] Implement client-side validation of block settings Active (see \Drupal\experience_builder\Plugin\ExperienceBuilder\ComponentSource\BlockComponent::fixBooleansUsingConfigSchema())
• etc.

This should be fixed before 1.0, but not necessarily before 🌱 Milestone 1.0.0-beta1: Start creating non-throwaway sites Active  — because A) ComponentSource plugins won't be a stable API yet, B) I don't see how this could impact the data storage.