[FIX] website_event: restore event list layout

Commit https://github.com/odoo/odoo/commit/b43364af7258e45ad846fbbf1f375ad26e58eb0d
introduced a row in a row. On a standard database, the bug is invisible.
When the user wants to edit that event list page, the right column... is
not on the right anymore.

Note: in 12.0, thanks to BS4, the bug was revealed even more as even on
a standard non-edited database, the bug is visible.

Closes https://github.com/odoo/odoo/pull/28693

addons/website_event/views/website_event_templates.xml

@@ -79,14 +79,14 @@
                         </li>
                     </ul>
                 </div>
-                <div class="row">
-                    <div class="col-sm-6 col-xs-offset-3">
-                        <t t-call="website.pager"/>
-                    </div>
-                </div>
                 <div class="col-md-3 oe_structure" id="right_column">
                 </div>
             </div>
+            <div class="row">
+                <div class="col-sm-6 col-xs-offset-3">
+                    <t t-call="website.pager"/>
+                </div>
+            </div>
         </div>
         <div class="oe_structure"/>
       </div>