[FIX] website_slides: count non-members views as public views
[FIX] website_slides: count non-members views as public views

Task #1940360
Subtask of #1902304

Purpose
=======

Slide views made by non-members of the channel (typically the website_publisher
designing the survey) should be counted in the "public_views".

closes odoo/odoo#31096
ygol/odoo,ygol/odoo,ygol/odoo,ygol/odoo,ygol/odoo,ygol/odoo,ygol/odoo