[BUGFIX] Show argument validation results in scheduler list

The scheduler module now shows validation errors for execute console
commands as messages in the backend. Previously changing the
configuration of a console commands arguments could lead to an exception
when the currently selected set of arguments was not parseable anymore
with the new configuration.
In some circumstances it was also possible to save a task without
supplying all required arguments, which rendered the backend module
non-functional because of the exception.

Catching the exception and providing the error message helps spotting
and fixing these errors without having to manipulate the database
directly.

Resolves: #89774
Releases: master, 9.5
Change-Id: I838e90bdd48f7146863630fa7dd09776459393d2
Reviewed-on: https://review.typo3.org/c/Packages/TYPO3.CMS/+/62756


Tested-by: TYPO3com <noreply@typo3.com>
Tested-by: Jörg Bösche <typo3@joergboesche.de>
Tested-by: Daniel Goerz <daniel.goerz@posteo.de>
Reviewed-by: Benni Mack <benni@typo3.org>
Reviewed-by: Jörg Bösche <typo3@joergboesche.de>
Reviewed-by: Daniel Goerz <daniel.goerz@posteo.de>