[BUGFIX] Marker missing for page.includeCSSLibs

The HTML templates are missing the marker for the
introduced page.includeCSSLibs TS feature in 6.2

Resolves: #57467
Releases: 6.2
Change-Id: I83d7c7f34fc83c4c699bad7edfaa03c6684497fe
Reviewed-on: https://review.typo3.org/28997
Reviewed-by: Georg Ringer
Tested-by: Georg Ringer