[BUGFIX] Escape title, extension, description of scheduler tasks

Properly escapes the title, description and extension of
displayed scheduler tasks

Resolves: #29179
Releases: 6.2, 6.1, 6.0, 4.7, 4.5
Change-Id: Ie03383f694863e435bfb96341226f8c78be426e5
Reviewed-on: https://review.typo3.org/25231
Reviewed-by: Stefan Neufeind
Tested-by: Stefan Neufeind