[FIX] gamification: avoid epty label in  email template
[FIX] gamification: avoid epty label in  email template

This fix hide the line "Next rank" when the user reached the last rank

closes odoo/odoo#48540

Signed-off-by: Jérémy Kersten (jke) <56923a0c9ca793c07ff1df1013de5694062a27a6@openerp.com>

ygol/odoo,ygol/odoo,ygol/odoo,ygol/odoo,ygol/odoo,ygol/odoo,ygol/odoo