*_ = hr_holidays

Step:
  - Install contract app
  - Create user with payroll manger access and None Employees
  - Login with new user and create contract
  - Click on employee field and click on Search More
Issue:
    When the user does not have access to the employee app and the search dialog accesses the
 employee during search more, so the traceback come.

Fix:
    If the user does not have access to the Employee application, public employee will be
  used in the search more dialog.

Why needed string insead of props.string:
   When we pass related modal in option then undefined appears in m2m search dialog instead
   of field label.

task-3366443

closes odoo/odoo#130050

Related: odoo/enterprise#44774
Signed-off-by: Sofie Gvaladze (sgv) <sgv@odoo.com>