[BUGFIX] Avoid undefined array key in AbstractPlugin::pi_exec_query

Resolves: #99158
Releases: main, 11.5
Change-Id: I7cc2760f7f7ec4f329e8ec2dac127da3b2ba9648
Reviewed-on: https://review.typo3.org/c/Packages/TYPO3.CMS/+/76762


Tested-by: core-ci <typo3@b13.com>
Tested-by: Stefan Bürk <stefan@buerk.tech>
Reviewed-by: Oliver Klee <typo3-coding@oliverklee.de>
Reviewed-by: Chris Müller <typo3@krue.ml>
Reviewed-by: Benni Mack <benni@typo3.org>
Reviewed-by: Georg Ringer <georg.ringer@gmail.com>
Tested-by: Benni Mack <benni@typo3.org>
Reviewed-by: Stefan Bürk <stefan@buerk.tech>