[DOCS] Fix typo in "Extension recordlist merged into backend"

Resolves: #98542
Related: #98535
Releases: main
Change-Id: Iacda5665031458eca739aa7d42b364ff66d57631
Reviewed-on: https://review.typo3.org/c/Packages/TYPO3.CMS/+/75999


Tested-by: Oliver Klee <typo3-coding@oliverklee.de>
Tested-by: core-ci <typo3@b13.com>
Tested-by: Georg Ringer <georg.ringer@gmail.com>
Reviewed-by: Oliver Klee <typo3-coding@oliverklee.de>
Reviewed-by: Georg Ringer <georg.ringer@gmail.com>