[TASK] Public DP in DateFormatterTest

Resolves: #100395
Related: #100249
Releases: main
Change-Id: Ida96df615efdeab4f735057a1ff597f7d7a280fe
Reviewed-on: https://review.typo3.org/c/Packages/TYPO3.CMS/+/78369


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