Fix typo in documentation

This closes https://github.com/select2/select2/issues/3213.

docs/examples.html

@@ -211,7 +211,7 @@ $(".js-example-data-array-selected").select2({
   data: data
 })
 
-<select class="js-example-data-array-selected"></select>
+<select class="js-example-data-array"></select>
 
 <select class="js-example-data-array-selected">
   <option value="2" selected="selected">duplicate</option>