[TASK] Clean up fixCopyAfterDuplFields

Rarely used fixCopyAfterDuplFields method in
DataHandler is cleaned up, since a couple of
arguments and options do no longer work due
to previous removals. Actually the method is
meanwhile only called once.

Resolves: #100506
Releases: main
Change-Id: I5396204943c14e1d867d9da8f5909725e50f40b0
Reviewed-on: https://review.typo3.org/c/Packages/TYPO3.CMS/+/78514


Tested-by: Christian Kuhn <lolli@schwarzbu.ch>
Reviewed-by: Christian Kuhn <lolli@schwarzbu.ch>
Tested-by: Benni Mack <benni@typo3.org>
Tested-by: core-ci <typo3@b13.com>
Reviewed-by: Benni Mack <benni@typo3.org>