[BUGFIX] ContentObjectRenderer still calls t3lib_div

When trying to determine which scheme to use for property
forceAbsoluteUrl, class ContentObjectRenderer calls
t3lib_div::getIndpEnv('TYPO3_SSL').
This must be replaced with GeneralUtility.

Resolves: #53530
Releases: 6.2
Change-Id: I7b7de9373fbbee3f981a28065a12d159eb37ca26
Reviewed-on: https://review.typo3.org/25276
Reviewed-by: Wouter Wolters
Tested-by: Wouter Wolters