[FIX] point_of_sale: hide receipt in the render container after print

Before this commit, the POS receipt was added to the bottom of the
page after printing. In some browsers, this caused overflow and made
the POS interface scrollable.

With this commit, we fix this issue by changing the position of the
receipt container to 'fixed'. This prevents the receipt from affecting
the layout of the page after printing, thus avoiding the overflow issue
and keeping the POS interface non-scrollable.

opw-3775808

closes odoo/odoo#156025

Signed-off-by: Joseph Caburnay (jcb) <jcb@odoo.com>

addons/point_of_sale/static/src/app/printer/render_service.js

@@ -10,7 +10,7 @@ export class RenderContainer extends Component {
     // place where to momentarily render some html code
     // we should only intact with that div through the `whenMounted` function
     static template = xml`
-        <div style="left: -1000px; position: absolute;">
+        <div style="left: -1000px; position: fixed;">
             <div t-ref="ref">
                 <t t-if="props.comp.component" t-component="props.comp.component" t-props="props.comp.props"/>
             </div>