[TASK] Allow Piwik PRO debug mode param '_stg_debug'

The URL param '_stg_debug' is needed to call the debug mode on-site

Resolves: #101613
Releases: main, 11.5, 12.4
Change-Id: Iff94ede5c3d388fe8b130e10e5b48658511a0bc3
Reviewed-on: https://review.typo3.org/c/Packages/TYPO3.CMS/+/80435


Reviewed-by: Oliver Klee <typo3-coding@oliverklee.de>
Tested-by: core-ci <typo3@b13.com>
Tested-by: Andreas Fernandez <a.fernandez@scripting-base.de>
Reviewed-by: Andreas Fernandez <a.fernandez@scripting-base.de>
Reviewed-by: Stefan B�rk <stefan@buerk.tech>
Tested-by: Stefan B�rk <stefan@buerk.tech>