Fix course staff/instructor ordering.

course_discovery/apps/publisher/templates/publisher/course_run/edit_run_form.html

@@ -220,7 +220,7 @@
                         <label class="field-label ">
                             {% trans "Search for Instructor:" %}
                         </label>
-                        <select name="staff" data-autocomplete-light-function="select2"
+                        <select name="instructor" data-autocomplete-light-function="select2"
                                 multiple="multiple" data-minimum-input-length="2"
                                 data-autocomplete-light-url="/admin/course_metadata/person-autocomplete/"
                                 id="id_staff" data-html="true" class="field-input">

course_discovery/apps/publisher/views.py

@@ -1020,7 +1020,7 @@ class CourseRunEditView(mixins.LoginRequiredMixin, mixins.PublisherPermissionMix
 
     def post(self, request, *args, **kwargs):
         user = request.user
-
+        staff = request.POST.getlist('staff')
         context = self.get_context_data()
         course_run = context.get('course_run')
         lms_course_id = course_run.lms_course_id
@@ -1044,7 +1044,8 @@ class CourseRunEditView(mixins.LoginRequiredMixin, mixins.PublisherPermissionMix
             try:
                 with transaction.atomic():
                     course_run = run_form.save(changed_by=user)
-                    run_form.save_m2m()
+                    course_run.staff.clear()
+                    course_run.staff.add(*staff)
 
                     # If price-type comes with request then save the seat object.
                     if seat_form and request.POST.get('type'):