[BUGFIX] Display error messages in scheduler

The scheduler exception handling on editing silently ignored most
exceptions. The one exception was a specific exception that did not
even exist anymore.

The handling was changed to only ignore those exceptions with existing
handling and adding messages for all others.

Resolves: #80299
Releases: master, 9.5
Change-Id: I9b2a91f244bec99deb79da93a4e33680e862d16c
Reviewed-on: https://review.typo3.org/c/Packages/TYPO3.CMS/+/63568


Tested-by: TYPO3com <noreply@typo3.com>
Tested-by: Benni Mack <benni@typo3.org>
Tested-by: Georg Ringer <georg.ringer@gmail.com>
Reviewed-by: Benni Mack <benni@typo3.org>
Reviewed-by: Georg Ringer <georg.ringer@gmail.com>