[BUGFIX] PHP 8.1 bugfix

Classes/Service/ExtensionSettingsService.php

@@ -59,7 +59,7 @@ class ExtensionSettingsService {
 				$configuration = unserialize($GLOBALS['TYPO3_CONF_VARS']['EXT']['extConf']['sg_youtube']);
 			}
 		} else {
-			$configuration = $GLOBALS['TYPO3_CONF_VARS']['EXTENSIONS']['sg_youtube'];
+			$configuration = $GLOBALS['TYPO3_CONF_VARS']['EXTENSIONS']['sg_youtube'] ?? [];
 		}
 
 		$setting = '';