A horizontal padding was applied to each media list item, making it impossible to make the media list items full width. Full width media list items can always be reduced by adding padding in the editor, but the converse is not true. For this reason, this commit applies horizontal padding 0 to each media list item in the snippet template. task-2716398 closes odoo/odoo#81637 Signed-off-by: David Monjoie (dmo) <dmo@odoo.com>