Update thumbnail.html

Author: in-session

app/code/Magento/Ui/view/base/web/templates/dynamic-rows/cells/thumbnail.html

@@ -4,4 +4,4 @@
  * See COPYING.txt for license details.
  */
 -->
-<img class="admin__control-thumbnail" style="max-height: 75px; max-width: 75px;" data-bind="attr: {src: $data.value}"/>
+<img class="admin__control-thumbnail" style="max-height: 75px; max-width: 75px;" data-bind="attr: {src: $data.value}" loading="lazy"/>