Ensure only a user in a leadership role can cancel an event for a patrol

[clue4]

Problem: Right now, any person logged in on an account and in a patrol can cancel events for that patrol, including accounts that are only scouts.
Solution: Ensure that only leadership type accounts (Patrol leaders, Scout Masters) can only cancel events

Specs:

• Only leadership roles can delete events in their patrol
  • patrol leaders including senior patrol leaders, assistant patrol leaders
  • scoutmasters including assistant scout masters

Additional:
Hoping this is as straightforward as hiding the cancel event button with maybe some additional frontend changes but if this takes you into the backend please let me know!

[KobeZ123]

The changes should be done in the 'cancel-event' branch and a backend 'cancel-event' branch was also made for the deleteEvent resolver.