MDL-27619: Prevent teachers from turning course Outcomes into site-wide ones

Similar to the issue which allowed teachers to create site-wide scales by editing a course-specific scale (MDL-24682), teachers could also promote a course-specific scale to a site-wide (standard) by editing it.  As with MDL-24682, removing the course ID check (leaving just the capability check) prevents this unauthorised creation of site-wide (standard) outcomes.
weekly release 1.9.19+
weekly release 1.9.19+
weekly release 1.9.19+