[BUGFIX] AddQueryStringMethod overwrites parameters

Uri parameters are overwritten when using both POST and GET parameters
with the addQueryStringMethod functionality of uri generation.

The problem is solved by using the method
GeneralUtility::array_merge_recursive_overrule() instead of array_merge
when merging the POST and GET parameters.

Resolves: #53450
Releases: 6.2
Change-Id: I39926ebbaa08f6810e440bad1f238aeb2af17e5b
Reviewed-on: https://review.typo3.org/25211
Reviewed-by: Xavier Perseguers
Tested-by: Xavier Perseguers
Tested-by: Wolfgang Wagner
Reviewed-by: Stefan Froemken
Tested-by: Stefan Froemken
Reviewed-by: Wouter Wolters
Tested-by: Wouter Wolters