Added a new module called Level for level testing

src/pages/(admin)/Lists/ExamList.tsx

@@ -20,6 +20,7 @@ const CLASSES: {[key in Module]: string} = {
 	listening: "text-ielts-listening",
 	speaking: "text-ielts-speaking",
 	writing: "text-ielts-writing",
+	level: "text-ielts-level",
 };
 
 const columnHelper = createColumnHelper<Exam>();