This PR adds the ability to destroy reviewables for a passed user via the API. This was not possible before as this action was reserved for reviewables for you created only.
If a user is an admin and calls the `#destroy` action from the API they are able to destroy a reviewable for a passed user. A user can be targeted by passed either their:
- username
- external_id (for SSO)
to the request.
In the case you attempt to destroy a non-personal reviewable and
- You are not an admin
- You do not access the `#destroy` action via the API
you will raise a `Discourse::InvalidAccess` (403) and will not succeed in destroying the reviewable.
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