Added missing dependency for ContentSection in FolderImExporter

ccm-cms/src/main/java/org/librecms/contentsection/FolderImExporter.java

@@ -51,7 +51,7 @@ public class FolderImExporter extends AbstractEntityImExporter<Folder> {
     @Override
     protected Set<Class<? extends Exportable>> getRequiredEntities() {
         return Set.of(
-//            ContentSection.class,
+            ContentSection.class,
             Category.class,
             Domain.class
         );