[TASK] Deprecate unused class MagicImageService

The class MagicImageService is deprecated, since
it's unused since version 10, due to removal of
EXT:rtehtmlarea.

Resolves: #99237
Releases: main
Change-Id: I2d03315a06abaf618e7cd8544a0ee1d06b1c1100
Reviewed-on: https://review.typo3.org/c/Packages/TYPO3.CMS/+/78662


Reviewed-by: Oliver Bartsch <bo@cedev.de>
Tested-by: Benni Mack <benni@typo3.org>
Reviewed-by: Benni Mack <benni@typo3.org>
Reviewed-by: Stephan Großberndt <stephan.grossberndt@typo3.org>
Tested-by: Oliver Bartsch <bo@cedev.de>
Tested-by: core-ci <typo3@b13.com>