[TASK] Remove superfluous typecasts in Extbase AbstractValidator

Function arguments for `addErrorForProperty()` in Extbase
`AbstractValidator` do use PHP native types, so several
typecasts in the function are not required any more.

Resolves: #102321
Releases: main, 12.4
Signed-off-by: Torben Hansen <derhansen@gmail.com>
Change-Id: Iecd9999735bdb9f7ca9b7bdc2432de6c30f1f98e
Reviewed-on: https://review.typo3.org/c/Packages/TYPO3.CMS/+/81692


Reviewed-by: Stefan Bürk <stefan@buerk.tech>
Tested-by: Simon Schaufelberger <simonschaufi+typo3@gmail.com>
Reviewed-by: Simon Schaufelberger <simonschaufi+typo3@gmail.com>
Tested-by: core-ci <typo3@b13.com>
Tested-by: Oliver Hader <oliver.hader@typo3.org>
Reviewed-by: Oliver Hader <oliver.hader@typo3.org>
Reviewed-by: Oliver Klee <typo3-coding@oliverklee.de>
Tested-by: Stefan Bürk <stefan@buerk.tech>
Tested-by: Oliver Klee <typo3-coding@oliverklee.de>