[BUGFIX] Correctly resolve nested arguments in SimpleEnhancer

Having `additionalParams = &simple[id]=okay&simple[other]=other`
with the following route enhancer configuration lead to some flaws:

    routeEnhancers:
      TestSimple:
        type: Simple
        routePath: '/simple/{simple_id}'
        _arguments:
          simple_id: 'simple/id'

* generated URI contained `simple__other`, not resolving nesting
  (`/simple/okay?simple__other=other&cHash=...`)
* `PageArguments::$staticArguments` contained parameter `simple_id`
  (unresolved to actual query parameter, incorrectly marked static)
* other `PageArguments` properties contained `simple__other`
  (unresolved to actual query parameter, ignored nesting)

Resolves: #91447
Releases: master, 10.4, 9.5
Change-Id: If96a6245f44a12d6e666d0ead8b1cc9cbbb43170
Reviewed-on: https://review.typo3.org/c/Packages/TYPO3.CMS/+/69227


Tested-by: core-ci <typo3@b13.com>
Tested-by: Benni Mack <benni@typo3.org>
Tested-by: Markus Klein <markus.klein@typo3.org>
Tested-by: Oliver Hader <oliver.hader@typo3.org>
Reviewed-by: Benni Mack <benni@typo3.org>
Reviewed-by: Markus Klein <markus.klein@typo3.org>
Reviewed-by: Oliver Hader <oliver.hader@typo3.org>