[BUGFIX] Restore FileInterface::setContents() TODO comments

Resolves: #103202
Releases: main, 12.4
Related: #40096
Change-Id: If64a5d16da9d500180d070b8d5f6a7fd96609010
Reviewed-on: https://review.typo3.org/c/Packages/TYPO3.CMS/+/83135


Tested-by: Stefan Bürk <stefan@buerk.tech>
Reviewed-by: Stefan Bürk <stefan@buerk.tech>
Tested-by: core-ci <typo3@b13.com>
Tested-by: Garvin Hicking <gh@faktor-e.de>
Reviewed-by: Christian Kuhn <lolli@schwarzbu.ch>
Tested-by: Christian Kuhn <lolli@schwarzbu.ch>
Reviewed-by: Andreas Kienast <a.fernandez@scripting-base.de>
Reviewed-by: Garvin Hicking <gh@faktor-e.de>
Tested-by: Andreas Kienast <a.fernandez@scripting-base.de>