docs: add note about sanitizer when using textTemplate

Author: ghiscoding

packages/demo/src/examples/example16.html

@@ -18,7 +18,7 @@ <h2 class="bd-title">
       </span>
     </h2>
     <div class="demo-subtitle">
-      Display avatar images by using <code>textTemplate</code> to render HTML with image src.
+      Display avatar images by using <code>textTemplate</code> to render HTML with image src. Note that the use of <code>sanitizer</code> with tools like DOM Purify is recommended when using <code>textTemplate</code>.
     </div>
   </div>
 </div>