Feature: #90265 - Show dispatched Events in Admin Panel

See forge#90265

Description

To promote the new PSR-14 Events and to make it easier for people to see which kinds of events may be used, the admin panel displays all events that are dispatched in the current request with their parameters.

Impact

The Admin Panel has a new section called "Events" (in "Debug") which shows all events with their respective values that have been dispatched during the current request. To allow smooth navigating of these objects, the symfony var-dumper component is used.