Fix for re-editing of change notes
Fix for re-editing of change notes

A change note can be edited until publication then a new change note
must be provided rather than showing the previous change note.

alphagov/specialist-publisher,alphagov/specialist-publisher,alphagov/specialist-publisher-rebuild,alphagov/specialist-publisher,alphagov/specialist-publisher-rebuild,alphagov/specialist-publisher-rebuild,ministryofjustice/specialist-publisher,alphagov/manuals-publisher,ministryofjustice/specialist-publisher,alphagov/manuals-publisher,ministryofjustice/specialist-publisher,ministryofjustice/specialist-publisher,alphagov/specialist-publisher-rebuild,alphagov/manuals-publisher