deleted calendar event is not identifiable

[diemelone]

It might be, that this is a duplicate, but I didn't really know what to search for but I tried...

Steps to reproduce

1. activate activity
2. create an event
3. delete an event

Expected behaviour

The notification should include at least the title of the event, more information like in #545 would be great to maybe even find mistakes.

Actual behaviour

XY deleted that event in calendar ZYX

Server configuration

Nextcloud version: (see Nextcloud admin page) 21.03 calendar 3.0 activity 2.14.3

Signing status: admin