[FIX] mail: adapt discuss mobile from cp refactoring
[FIX] mail: adapt discuss mobile from cp refactoring

Since a recent ControlPanel/Search view refactoring [1],
all client actions must be adapted [2]. Discuss was updated,
but not discuss mobile, which this commit fixes.

[1] https://github.com/odoo/odoo/commit/4cd379cf6ecffa00e0085a9833228128b484d48a
[2] https://github.com/odoo/odoo/commit/b1ef0001f61d29fc3d3be384422c0fb35a09806f

Task-ID 1918722

closes odoo/odoo#29601
ygol/odoo,ygol/odoo,ygol/odoo,ygol/odoo,ygol/odoo,ygol/odoo,ygol/odoo