using const instead of let keyword for createRange() (#32739)

using const instead of let keyword

files/en-us/web/api/document/createrange/index.md

@@ -28,7 +28,7 @@ The created {{domxref("Range")}} object.
 ## Examples
 
 ```js
-let range = document.createRange();
+const range = document.createRange();
 
 range.setStart(startNode, startOffset);
 range.setEnd(endNode, endOffset);