[TASK] Migrate TYPO3_MODE usage

Classes/Service/AbstractParserService.php

@@ -26,6 +26,7 @@ namespace SGalinski\ContentReplacer\Service;
  ***************************************************************/
 
 use SGalinski\ContentReplacer\Repository\TermRepository;
+use TYPO3\CMS\Core\Http\ApplicationType;
 use TYPO3\CMS\Core\Utility\GeneralUtility;
 use TYPO3\CMS\Extbase\Configuration\BackendConfigurationManager;
 use TYPO3\CMS\Frontend\ContentObject\ContentObjectRenderer;
@@ -105,7 +106,8 @@ abstract class AbstractParserService {
 		}
 
 		if ($stdWrap !== '') {
-			if (TYPO3_MODE === 'BE') {
+			$applicationType = GeneralUtility::makeInstance(ApplicationType::class);
+			if ($applicationType->isBackend()) {
 				$configurationManager = GeneralUtility::makeInstance(BackendConfigurationManager::class);
 				$extbaseFrameworkConfiguration = $configurationManager->getTypoScriptSetup();
 				$typoscriptConfiguration = $extbaseFrameworkConfiguration['plugin.']['tx_content_replacer.'][$stdWrap . '.'];