[FIX] website: prevent redirect loop on / if no homepage

Since 3d65424708d, if the homepage does not exists (no page with '/' as URL,
no page set as homepage), it would loop between / controller and _serve_page.

task-2250381

closes odoo/odoo#59548

X-original-commit: 07b701c581bd960bed42fcf97fae0dfed0332656
Signed-off-by: Jérémy Kersten (jke) <jke@openerp.com>
Signed-off-by: Romain Derie <rdeodoo@users.noreply.github.com>

addons/website/models/ir_http.py

@@ -251,7 +251,7 @@ class Http(models.AbstractModel):
         page = request.env['website.page'].sudo().search(published_domain, order='website_id asc', limit=1)
 
         # redirect withtout trailing /
-        if not page and req_page.endswith("/"):  # / handled by controller
+        if not page and req_page != "/" and req_page.endswith("/"):
             return request.redirect(req_page[:-1])
 
         if page: