[TASK] Have static DP in VimeoHelperTest

Clean up a bit along the way.

Resolves: #100394
Related: #100249
Releases: main
Change-Id: I4a9395f5f96f129b3673dfbf870ee88bb531763b
Reviewed-on: https://review.typo3.org/c/Packages/TYPO3.CMS/+/78368


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