[FIX] base: correct Model Overview report

Since 3d04e448, the reports must start with a `article` class, not `page`.
The report was not adapted.

Fixes #20066

odoo/addons/base/ir/report_ir_model.xml

@@ -3,7 +3,7 @@
 <template id="report_irmodeloverview">
     <t t-call="report.html_container">
         <t t-foreach="docs" t-as="o">
-            <div class="page">
+            <div class="article">
                 <table class="table table-bordered mb64">
                     <tr>
                         <td colspan="12">