For FTP-based SIS integrations, show the file date of the most recent uploaded file

This would be helpful to know if the application is not receiving new data from the SIS. If no new data was received after X days, the SIS sync task should probably fail and the date of the last upload could be shown in the status for SIS Integration in the footer.

Additionally, maybe send an email notification to admins or Eduready360 to alert them of an issue.