[TASK] Extend DataHandler IRRE functional tests

* create and copy
* create and localize
* modify and discard
* create and copy and discard
* create and localize and discard

Resolves: #56072
Releases: 6.2
Change-Id: Iead056883f7bbb2072a0bd082b05094d7d46101d
Reviewed-on: https://review.typo3.org/27693
Reviewed-by: Oliver Hader
Tested-by: Oliver Hader