* added new api route /event-types/bySlug/{slug}
* refactor: schema query slug
* refactor: event-types/bySlug to event-types/by-slug route
* feat: allow admins to fetch event types on behalf of others
* fix: auth middleware
* added slug query param to main event-type api route
* removed the /by-slug route
* refactor logic
* remove unwanted changes
* updated swagger api doc
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Co-authored-by: supalarry <lauris.skraucis@gmail.com>