Refactor test_initial_data test.
Refactor test_edit test.
Refactor test_publish test.
Refactor test_unpublish test.
Refactor test_published_at_publish test.
Fix test_published_date_is_not_changed_when_publishing_twice.
Refactor test_delete test.
Refactor test_delete_published test.
Refactor test_revert test.
Refactor test_actions_on_published test.
Refactor signal tests.