Use bulk unpublish api hook

Problem/Motivation

This is related to safedelete. Investigating
EntityStorageException: An existing default revision of the 'node' entity type can not be changed to a non-default revision. in Drupal\Core\Entity\Sql\SqlContentEntityStorage->save() (line 815 of core/lib/Drupal/Core/Entity/Sql/SqlContentEntityStorage.php

Turns out we forgot to implement this hook in moderated_content_bulk_publish.
Requires latest release of moderated_content_bulk_publish.

Steps to reproduce

bulk unpublish a published node

Proposed resolution

see commit

Remaining tasks

publish safedelete 1.0.85 and moderated_content_bulk_publish 2.0.50

User interface changes

Support bulk unpublish

API changes

add api

Data model changes

None