Generate a list of top-level classes that use @inheritdoc but inherit nothing.

Problem/Motivation

{@inheritdoc} appears quite frequently in the documentation, but not always because the docs inheritance is broken. Instead, the inheritance works just fine, but the top-level class uses @inheritdoc to document its methods, which flows down to its children.

To aid documentation efforts on Drupal core, let's use Doctum's extensibility and hackability to generate a list of classes that are causing this problem, and open an issue on Drupal core's issue queue to get these issues resolved.

If during the course of research for this task we discover that something is wrong with Doctum's @inheritdoc inheritance features, let's document that here so we can work on it.

Steps to reproduce

Proposed resolution

Remaining tasks

User interface changes

API changes

Data model changes