[BUGFIX] RootlineUtility does not consider foreign_sorting

Make sure RootlineUtility::enrichWithRelationFields() does take
the TCA setting foreign_sorting into account when fetching
foreign data for the rootline cache.

Resolves: #54884
Releases: 6.2, 6.1
Change-Id: I6f8323bd5a99f9009820332c220a5637e0930712
Reviewed-on: https://review.typo3.org/26971
Reviewed-by: Markus Klein
Tested-by: Markus Klein