Bug when existing project hours user doesn't have 'can_clock_in' permission

[ghost]

The schedule edit page doesn't render correctly if a ProjectHours user somehow doesn't have the can_clock_in permission.

If a user that has associated ProjectHours somehow loses the can_clock_in permission, they are not included in the all_users data sent to the front end, and a JavaScript error occurs.

Workaround for now is for all users who have ever had ProjectHours to keep the can_clock_in permission. Their user account can be set to active = False if they leave the company, which prevents them from logging in or clocking time.