[FIX] account: only display qr code if residual > 0

In case an invoice is already paid it is useless to provide
a QR Code for scanning to pay a residual of zero.

closes odoo/odoo#78437

X-original-commit: bfb5bcc07465240b0952e031522dd513dff8c2ab
Signed-off-by: oco-odoo <oco-odoo@users.noreply.github.com>

addons/account/views/report_invoice.xml

@@ -173,7 +173,7 @@
                     <p t-if="o.invoice_incoterm_id" name="incoterm">
                         <strong>Incoterm: </strong><span t-field="o.invoice_incoterm_id.code"/> - <span t-field="o.invoice_incoterm_id.name"/>
                     </p>
-                    <div id="qrcode" t-if="o.display_qr_code">
+                    <div id="qrcode" t-if="o.display_qr_code and o.amount_residual > 0">
                         <p t-if="qr_code_urls.get(o.id)">
                             <strong class="text-center">Scan me with your banking app.</strong><br/><br/>
                             <img class="border border-dark rounded" t-att-src="qr_code_urls[o.id]"/>