[BUG] Call to a member function getSolrConfiguration() on null

[eliashaeussler]

Describe the bug
When running an upgrade wizard for EXT:container, I run into issues with EXT:solr due to missing site configuration.

Stack trace:

$ vendor/bin/typo3cms container_deleteChildrenWithWrongPid
                                                            
  [ Error ]                                                 
  Call to a member function getSolrConfiguration() on null  
                                                            
Exception trace:
#0 ()
   typo3conf/ext/solr/Classes/Domain/Index/Queue/GarbageRemover/AbstractStrategy.php:118
#1 ApacheSolrForTypo3\Solr\Domain\Index\Queue\GarbageRemover\AbstractStrategy->deleteIndexDocuments()
   typo3conf/ext/solr/Classes/Domain/Index/Queue/GarbageRemover/AbstractStrategy.php:96
#2 ApacheSolrForTypo3\Solr\Domain\Index\Queue\GarbageRemover\AbstractStrategy->deleteInSolrAndUpdateIndexQueue()
   typo3conf/ext/solr/Classes/Domain/Index/Queue/GarbageRemover/PageStrategy.php:50
#3 ApacheSolrForTypo3\Solr\Domain\Index\Queue\GarbageRemover\PageStrategy->collectPageGarbageByContentChange()
   typo3conf/ext/solr/Classes/Domain/Index/Queue/GarbageRemover/PageStrategy.php:32
#4 ApacheSolrForTypo3\Solr\Domain\Index\Queue\GarbageRemover\PageStrategy->removeGarbageOfByStrategy()
   typo3conf/ext/solr/Classes/Domain/Index/Queue/GarbageRemover/AbstractStrategy.php:63
#5 ApacheSolrForTypo3\Solr\Domain\Index\Queue\GarbageRemover\AbstractStrategy->removeGarbageOf()
   typo3conf/ext/solr/Classes/Domain/Index/Queue/UpdateHandler/GarbageHandler.php:78
#6 ApacheSolrForTypo3\Solr\Domain\Index\Queue\UpdateHandler\GarbageHandler->collectGarbage()
   typo3conf/ext/solr/Classes/Domain/Index/Queue/UpdateHandler/EventListener/ImmediateProcessingEventListener.php:138
#7 ApacheSolrForTypo3\Solr\Domain\Index\Queue\UpdateHandler\EventListener\ImmediateProcessingEventListener->handleRecordDeletedEvent()
   typo3conf/ext/solr/Classes/Domain/Index/Queue/UpdateHandler/EventListener/ImmediateProcessingEventListener.php:53
#8 ApacheSolrForTypo3\Solr\Domain\Index\Queue\UpdateHandler\EventListener\ImmediateProcessingEventListener->__invoke()
   typo3/sysext/core/Classes/EventDispatcher/EventDispatcher.php:51
#9 TYPO3\CMS\Core\EventDispatcher\EventDispatcher->dispatch()
   typo3/sysext/adminpanel/Classes/Service/EventDispatcher.php:41
#10 TYPO3\CMS\Adminpanel\Service\EventDispatcher->dispatch()
   typo3conf/ext/solr/Classes/GarbageCollector.php:85
#11 ApacheSolrForTypo3\Solr\GarbageCollector->processCmdmap_preProcess()
   typo3/sysext/core/Classes/DataHandling/DataHandler.php:3156
#12 TYPO3\CMS\Core\DataHandling\DataHandler->process_cmdmap()
   typo3conf/ext/container/Classes/Integrity/IntegrityFix.php:49
#13 B13\Container\Integrity\IntegrityFix->deleteChildrenWithWrongPid()
   typo3conf/ext/container/Classes/Updates/ContainerDeleteChildrenWithWrongPid.php:86
#14 B13\Container\Updates\ContainerDeleteChildrenWithWrongPid->executeUpdate()
   app/vendor/helhum/typo3-console/Classes/Console/Install/Upgrade/UpgradeWizardExecutor.php:67
#15 Helhum\Typo3Console\Install\Upgrade\UpgradeWizardExecutor->executeWizard()
   app/vendor/helhum/typo3-console/Classes/Console/Install/Upgrade/UpgradeHandling.php:142
#16 Helhum\Typo3Console\Install\Upgrade\UpgradeHandling->runWizard()
   app/vendor/helhum/typo3-console/Classes/Console/Install/Upgrade/UpgradeHandling.php:111
#17 Helhum\Typo3Console\Install\Upgrade\UpgradeHandling->runWizards()
   app/vendor/helhum/typo3-console/Classes/Console/Command/Upgrade/UpgradeRunCommand.php:143
#18 Helhum\Typo3Console\Command\Upgrade\UpgradeRunCommand->execute()
   app/vendor/symfony/console/Command/Command.php:298
#19 Symfony\Component\Console\Command\Command->run()
   app/vendor/symfony/console/Application.php:1040
#20 Symfony\Component\Console\Application->doRunCommand()
   app/vendor/helhum/typo3-console/Classes/Console/Mvc/Cli/Symfony/Application.php:189
#21 Helhum\Typo3Console\Mvc\Cli\Symfony\Application->doRunCommand()
   app/vendor/symfony/console/Application.php:301
#22 Symfony\Component\Console\Application->doRun()
   app/vendor/symfony/console/Application.php:171
#23 Symfony\Component\Console\Application->run()
   app/vendor/helhum/typo3-console/Classes/Console/Core/Kernel.php:118
#24 Helhum\Typo3Console\Core\Kernel->handle()
   app/vendor/helhum/typo3-console/Scripts/typo3-console.php:18
#25 {closure}()
   app/vendor/helhum/typo3-console/Scripts/typo3-console.php:20
#26 require()
   app/vendor/helhum/typo3-console/typo3cms:3
#27 include()
   app/vendor/bin/typo3cms:119

Used versions (please complete the following information):

• TYPO3 Version: 11.5.30
• Browser: CLI
• EXT:solr Version: 11.5.3
• Used Apache Solr Version: not relevant
• PHP Version: 8.1.21
• MySQL Version: 8.0.34

Additional context
There's already #3597 which addresses a similar issue, but the related fix is applied to another class. I'll provide a PR to fix the bug in the AbstractStrategy class.