MDL-52811 course: Note about the new capability when creating courses

course/upgrade.txt

 This files describes API changes in /course/*,
 information provided here is intended especially for developers.
 
+=== 3.5 ===
+ * There is a new capability 'moodle/course:forcelanguage' to control which users can force the course
+   language; create_course and update_course functions delegate access control to the caller code; if you
+   are calling those functions you may be interested in checking if the logged in user has 'moodle/course:forcelanguage' capability.
+
 === 3.3 ===
 
  * External function core_course_external::get_courses_by_field now returns the course filters list and status.