Add an equivalent EntityConstraintViolationList for config entities

Problem/Motivation

EntityConstraintViolationList is typed to only work with FieldableEntityInterface entities.
Now we're slowly introducing validation for config objects it would be nice to have a constraint violation list for config entities to allow keeping the scope of the entity validated alongside the list of violations.

Steps to reproduce

Proposed resolution

Remaining tasks

User interface changes

Introduced terminology

API changes

Data model changes

Release notes snippet