bug: course_backup_task fails because of new backup_manager::create_course_backup interface

[KBorm]

The function course_backup_task::execute calls backup_manager::create_course_backup:

        backup_manager::create_course_backup($courseid);

But the signature has been changed in the meantime.

       public static function create_course_backup($courseid, $stepid)

As a result the task will always fail.

[KBorm]

there seems to be no test case that covers this code

[bluetom]

The bug should be fixed in the main branch now and the fix will be a part of the next release in one or two weeks.
A phpunit test for the step would be great!