chore(docs): update Editor TOC

hawkeye64 · hawkeye64 · commit 6e5dab35b614 · 2021-09-19T08:32:59.000-06:00
diff --git a/docs/src/pages/developing/using-qmarkdown.md b/docs/src/pages/developing/using-qmarkdown.md
@@ -232,6 +232,8 @@ The rest of the plugins are custom with QMarkdown or deemed necessary (like the
   codepen-title="QMarkdown"
 />
 
+## Advanced
+
 ### Editor
 <example-viewer
   title=""
