[FIX] website: access website in multi-company

- Create 2 companies A & B
- Create a website A
- Create a user U with access to company B only
- Connect as U and go to the website

An internal server error is raised.

This is due to 7bfcb53d which verifies if the user isn't
granted access to companies he is not supposed to access.

This is exactly what was done before this commit: the website is in a
company not allowed to the user.

opw-2116539

closes odoo/odoo#39921

Signed-off-by: Nicolas Martinelli (nim) <nim@odoo.com>