After the update of the bootstrap lib, the kanban records to be found in the menu Project Stages of Project > Configuration (after activation of a setting option) had each two weird borders. Here, we simplify the kanban-box template in order to get only one border as it is in 15.0. closes odoo/odoo#102249 X-original-commit: 839bdd0a853f88bfaeb0dd698d60e2168dc54188 Signed-off-by: Aaron Bohy (aab) <aab@odoo.com>