It is possible for a cron to be executed twice at a same moment if the cron is currently being executed by a cron worker and that a user click on the "run manually" button from its form view. closes odoo/odoo#157203 X-original-commit: a45f171eabdb571465d6245bf2a6bccecab53fa0 Signed-off-by: Olivier Dony (odo) <odo@odoo.com> Signed-off-by: Julien Castiaux (juc) <juc@odoo.com>