While this change is not 100% required now, it's good habit
and we are checking for it since Moodle 4.4.
All the changes in this commit have been applied automatically
using the moodle.PHPUnit.TestReturnType sniff and are, exclusively
adding the ": void" return types when missing.
Two new scheduled tasks, show_started_courses_task and
hide_ended_courses_task have been added, to automatically change
the course visibility when the start/end course date match the
current one.
They are disabled by default, to keep the current behaviour.
When admins enable any of them, they are executed once per
day by default (around midnight).
These scheduled tasks are based on the "CUL Course Visibility Update"
third-party plugin created by Tim Gagen and refactored and currently
maintained by Amanda Doughty:
https://moodle.org/plugins/local_culcourse_visibility
Thanks!! :-)
Andrew Nicols