[FIX] sale: portal SO view no image if public

Access a SO with the access token, without being logged

Before this commit, the images of the so lines were the no image placeholder
This was because the route of the image was so.line/product_image
Since the token applies on SO, and not on its lines, nothing simple would work

After this commit, we hide the image if the user is the public one

OPW 1868916
closes #25973

addons/sale/views/sale_portal_templates.xml

@@ -237,12 +237,13 @@
               </div>
               <t t-foreach="order.order_line" t-as="ol">
                 <div class="row orders_vertical_align">
-                    <div class="visible-lg col-lg-1 text-center">
+                    <div t-if="not request.env.user._is_public()" class="visible-lg col-lg-1 text-center">
                       <span t-field="ol.product_image" t-options="{'widget': 'image', 'class': 'img-rounded', 'style':'width: 48px;height:48px'}" />
                     </div>
                     <div id='product_name' class="col-lg-4 col-sm-6 col-xs-3">
                       <span t-esc="ol.product_id.name"/>
                     </div>
+                    <div t-if="request.env.user._is_public()" class="visible-lg col-lg-1 text-center" /> <!-- Just for alignment -->
                   <div class="col-xs-3 text-right">
                     <span t-field="ol.price_unit" t-options='{"widget": "monetary", "display_currency": order.pricelist_id.currency_id}'/>
                   </div>