[TASK] Simplify FE functional test related TypoScriptInstruction

Raised testing-framework allows avoiding usage of the
deprecated TemplateService::class identifier when adding FE
functional test related sub requests with special TypoScript.

> composer u typo3/testing-framework

Resolves: #98968
Releases: main
Change-Id: Ia7034701ab85d3cca6f5af95e9e25cf55568d8b5
Reviewed-on: https://review.typo3.org/c/Packages/TYPO3.CMS/+/76382


Tested-by: Stefan Bürk <stefan@buerk.tech>
Tested-by: core-ci <typo3@b13.com>
Tested-by: Nikita Hovratov <nikita.h@live.de>
Reviewed-by: Stefan Bürk <stefan@buerk.tech>
Reviewed-by: Nikita Hovratov <nikita.h@live.de>