keep the +/- before the price, to correctly highlight the fact that it's an additional price. closes odoo/odoo#102245 X-original-commit: 32a2379b34b8646b681d3e42412bbc1ce2a045f1 Related: odoo/enterprise#32319 Signed-off-by: Victor Feyens (vfe) <vfe@odoo.com>