[BUGFIX] Fix array access error in LinkAnalyzerResult

Doctrine dbal function fetchAssociative() was used in combination
with accessing an array element without null colesce.

Resolves: #103423
Releases: main, 12.4, 11.5
Change-Id: I6f5842f28722dc8b2716533e818fc40ed2fc25ef
Reviewed-on: https://review.typo3.org/c/Packages/TYPO3.CMS/+/83661


Reviewed-by: Stefan Bürk <stefan@buerk.tech>
Tested-by: core-ci <typo3@b13.com>
Tested-by: Stefan Bürk <stefan@buerk.tech>