[BUGFIX] Fix PHP 8 warning in ExtendedTemplateService

The method getTemplateQueryBuilder has a reference to
$GLOBALS['BE_USER']->workspace. This value should be
fetched via the WorkspaceAspect.

Resolves: #99795
Releases: 11.5
Change-Id: Ia5444b582da7436ab653923bbd8f91d87710a7b8
Reviewed-on: https://review.typo3.org/c/Packages/TYPO3.CMS/+/77670


Reviewed-by: Oliver Klee <typo3-coding@oliverklee.de>
Tested-by: Christian Kuhn <lolli@schwarzbu.ch>
Reviewed-by: Christian Kuhn <lolli@schwarzbu.ch>
Reviewed-by: Benni Mack <benni@typo3.org>
Tested-by: core-ci <typo3@b13.com>
Tested-by: Benni Mack <benni@typo3.org>