Incomplete task configuration breaks the backend module
If you create a new task, which should execute a console command, you have to save it before you can fill in the necessary arguments. If you now close the form, you can no longer call the Scheduler Backend module. The Symfony class "Input" throws a Symfony\Component\Console\Exception\RuntimeException because not all necessary arguments are set.
Steps to reproduce:
1. Click the "Add task" button inside the scheduler module
2. Select class "Execute console commands", select either type single or specify a frequency.
3. Select a "Schedulable Command" that has a required argument
4. Click "Save and close" (or save first and close the form after saving)
5. Scheduler module is broken now :(