[BUGFIX] Properly soft-delete scheduler task groups

Use update() over delete() to set hidden
field to 1 to soft-delete instead of
completely removing the row from DB

Resolves: #100251
Related: #99874
Releases: main
Change-Id: I8bc8a8c26e3f1918f253019604b7131eafa7e961
Reviewed-on: https://review.typo3.org/c/Packages/TYPO3.CMS/+/78210


Reviewed-by: Nikita Hovratov <nikita.h@live.de>
Tested-by: Stefan Bürk <stefan@buerk.tech>
Reviewed-by: Stefan Bürk <stefan@buerk.tech>
Tested-by: Nikita Hovratov <nikita.h@live.de>
Tested-by: core-ci <typo3@b13.com>