[IMP] http_routing: support redirect of double slash in middle of path

Move code to support only the redirect from url containing double '/' in
the middle of the path.
Keep same behavior than v15 and default Apache behavior.

domain.com//shop/product/1 -> 404
domain.com/shop//product/1 -> 301 -> /shop/product/1

opw-3063387

closes odoo/odoo#105936

X-original-commit: 0c6a474202970daebd232c16edb8cf7bf872a918
Signed-off-by: Julien Castiaux <juc@odoo.com>
Signed-off-by: Jérémy Kersten <jke@odoo.com>