[FIX] web: reload from attachment not working properly with basic layout in reports

when user create a report using basic layout and at download time, it gives warning that
the template doesn't contain the attributes 'data-oe-model' and 'data-oe-id' on
the div with the 'article class name so this issue is fixed in this commit.

closes odoo/odoo#56511

X-original-commit: c58400a1d27f0994a620108af476813bf654e879
Related: odoo/enterprise#12658
Signed-off-by: Damien Bouvy (dbo) <dbo@odoo.com>

addons/web/views/report_templates.xml

@@ -387,6 +387,7 @@
 
     <template id="basic_layout">
         <t t-call="web.html_container">
+            <t t-if="not o" t-set="o" t-value="doc"/>
             <div class="article" t-att-data-oe-model="o and o._name" t-att-data-oe-id="o and o.id" t-att-data-oe-lang="o and o.env.context.get('lang')">
                 <t t-raw="0"/>
             </div>