Fix template to prevent icons from duplicating

Closes #3487531

templates/layout-paragraphs-builder-component-menu--mercury-editor.html.twig

@@ -35,7 +35,13 @@
 			{% for type in types.content %}
 				<div class="lpb-component-list__item type-{{type.id}}">
 					<a{{type.link_attributes.setAttribute('href',type.url)}}>
-						{% if type.image %}<img src="{{ type.image }}" alt=""/>
+						{% if type.image %}
+						<style>
+							.lpb-component-list__item.type-{{ type.id }} a::before {
+								background: url({{ type.image }});
+								background-size: cover;
+							}
+						</style>
 						{% endif %}
 						{{ type.label }}</a>
 				</div>