[TASK] Remove unused internal methods in ResourceFactory

Removes two unused internal methods, which
were only kept for backwards compatibility.

Resolves: #105232
Releases: main
Change-Id: I95511a0d46c1c659c2c0e014b5043da57c4b8523
Reviewed-on: https://review.typo3.org/c/Packages/TYPO3.CMS/+/86492


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>