[FIX] web: no content helper style in list view with search panel

The list view has recently been rewritten in OWL (see 48ef812).
During the rewriting, it was forgotten to put the class o_renderer on
list renderers, making a no content helper in a list view be positioned
too much on the left and have its style broken when the list has a search
panel.

Part-of: odoo/odoo#97876

addons/web/static/src/views/list/list_renderer.xml

@@ -3,7 +3,7 @@
 
     <t t-name="web.ListRenderer" owl="1">
         <div
-            class="o_list_renderer"
+            class="o_list_renderer o_renderer"
             t-att-class="{'table-responsive': showTable}"
             t-attf-class="{{ props.archInfo.className or '' }}"
             tabindex="-1"