Delete event

[etkndr]

• [x] Clicking the "Delete" button on an event's details page will open a confirmation modal popup window that should contain: a Title: "Confirm Delete", a Message: "Are you sure you want to remove this event?", a Red button: "Yes (Delete Event)", and a Dark grey button: "No (Keep Event)".
• [x] Clicking the "Delete" button on the event's detail page should not delete the event. Clicking the "Yes (Delete Event)" button in the confirmation modal should delete the event.
• [x] After an event is deleted, it should be removed from the event list in the group's detail page and in the event list page. No refresh should be necessary.
• [x] After an event is deleted, the user should automatically be navigated to the group details page for the group associated with the deleted event.