Before this commit, creating a new leave as an officer from the approval tab would have by default no time off type, resulting in "Employee on False" in the display_name. After this commit, the display_name will set "on Time Off" instead of "on False" when there is no Time Off Type set. task-3054318 closes odoo/odoo#104963 Signed-off-by: Kevin Baptiste <kba@odoo.com>