*: website_blog, website_event, website_forum, website_livechat,
website_sale, website_sale_slides, website_slides, website_slides_forum
The goal of this commit is to adapt the website "new content" form
views to OWL.
Follows the merge of the "website in backend" task at [1].
[1]: 31cc10b91d
task-2687506
Part-of: odoo/odoo#96346