This class is a pre-defined system task which runs a security
scan every day at midnight. The scan consists of the following
1) Disable expired user accounts
2) Expire user passwords
3) Expire CSP session tokens
This defines the user-visible name of this task; This is defined in subclasses.
This method is responsible for executing the task.
At the scheduled time, the Task Manager creates an instance of this object, sets any property values using the stored "settings" for the task, and then invokes this method to execute the task.