OZG-5044 Refactored in SettingService

src/main/java/de/ozgcloud/admin/settings/SettingService.java

@@ -26,6 +26,6 @@ class SettingService {
 
 	private PostfachSettingBody getSettingWithPostfachFromDb() {
 		var postfach = repository.findOneByName(POSTFACH_SETTING_ITEM_NAME);
-		return postfach.isPresent() ? (PostfachSettingBody) postfach.get().getSettingBody() : PostfachSettingBody.builder().build();
+		return postfach.map(Setting::getSettingBody).map(PostfachSettingBody.class::cast).orElse(PostfachSettingBody.builder().build());
 	}
 }