`generate_control_function` should check `isscheduled`

[AayushSabharwal]

Currently generate_control_function assumes the system is simplified if it is marked as complete, which isn't true. It should probably use isscheduled.

[ChrisRackauckas]

This issue has already been resolved in commit eb3af92. The function now correctly uses isscheduled(sys) instead of iscomplete(sys) on line 203 of src/inputoutput.jl.

The fix was made as part of commit "fix: check isscheduled in generate_control_function instead of iscomplete".

This issue can be closed.