[BUGFIX] Fix some issues in the code discovered with phpstan

Classes/Controller/PluginController.php

@@ -143,8 +143,6 @@ class PluginController {
 	protected function getConfigurationManager(): ConfigurationService {
 		/** @var ConfigurationService $configurationManager */
 		$configurationManager = GeneralUtility::makeInstance(ConfigurationService::class);
-		$configurationManager->injectControllerContext($this);
-
 		return $configurationManager;
 	}