fixes #6516 - various product deletion fixes

* Redhat products & promoted products could be deleted under bulk actions api & ui
* Single product delete api allowed redhat & promoted product deletion
* cp_id was being sent up for bulk actions
* error messages were only including a single errored product
* success and error messages were not actually printing
* products were removed from list even if they were not actually deleted
I think this
```self.published_content_views.empty?```
has been addressed in https://github.com/Katello/katello/pull/4395