Prior to this commit, we may have left lingering podcast entries that
required manual cleanup. As a bonus, I also added deleting podcasts
when we delete users.
Closesforem/forem#18041
In addition I adjusted rubocop to not complain about the require method call
```
spec/services/users/delete_spec.rb:1:1: C: \
Style/TopLevelMethodDefinition: \
Do not define methods at the top-level. \
(https://rubystyle.guide#top-level-methods)
require "rails_helper"
^^^^^^^^^^^^^^^^^^^^^^
```
* remove comment and article docs when they are deleted
* fix banish user spec to handle ES deletes
* remove comments from elasticsearch when deleted via delete comments service
