[!!!][TASK] Remove deprecated Signals from SignalSlot Dispatcher

This change removes all triggers ("SlotReplacement classes") to Signals
that were used until TYPO3 v10 LTS.

The SignalSlot Dispatcher still stay for the time being, but it is unused in
TYPO3 Core now.

Resolves: #91474
Related: #91473
Releases: master
Change-Id: I08867cb5837f605e52a067457a91f40288556fab
Reviewed-on: https://review.typo3.org/c/Packages/TYPO3.CMS/+/64578


Tested-by: TYPO3com <noreply@typo3.com>
Tested-by: Andreas Fernandez <a.fernandez@scripting-base.de>
Tested-by: Wouter Wolters <typo3@wouterwolters.nl>
Tested-by: Benni Mack <benni@typo3.org>
Reviewed-by: Andreas Fernandez <a.fernandez@scripting-base.de>
Reviewed-by: Wouter Wolters <typo3@wouterwolters.nl>
Reviewed-by: Benni Mack <benni@typo3.org>