[FIX] mail: scrollbar for emoji
[FIX] mail: scrollbar for emoji

Open discuss on mobile phone, click on the smiley icon, not all smileys
are visible on screen.

opw-2030315

closes odoo/odoo#35146

Signed-off-by: Julien Castiaux <88a92cdf1aef33f8a03de5e3b866f7bcc2fd53f9@users.noreply.github.com>
ygol/odoo,ygol/odoo,ygol/odoo,ygol/odoo,ygol/odoo,ygol/odoo,ygol/odoo