Execute submission transfer rejection as super admin

Fixing: https://trello.com/c/L56qXscy/637-bug-agrupaci%C3%B3-xinxetes-sumat-submissions-que-no-pasen-a-estat-de-rejected

Rejecting a transfer submission implies writing on crm.lead entry. You must be super user (at least logged in on odoo with write permission on lead)