[BUGFIX] Avoid PHP 8.1 warning passing null format to DateViewHelper

Resolves: #96954
Releases: main, 11.5
Change-Id: I60366ca5155c96ccc1068cc48339b0e96318d5f8
Reviewed-on: https://review.typo3.org/c/Packages/TYPO3.CMS/+/73589


Reviewed-by: Oliver Klee <typo3-coding@oliverklee.de>
Reviewed-by: Stefan Bürk <stefan@buerk.tech>
Reviewed-by: Christian Kuhn <lolli@schwarzbu.ch>
Tested-by: Stefan Bürk <stefan@buerk.tech>
Tested-by: core-ci <typo3@b13.com>
Tested-by: Christian Kuhn <lolli@schwarzbu.ch>