Notify user if backup fails

[harryjackson1221]

Is your feature request related to a problem? Please describe.
When a backup does not complete, a user is not notified of a problem.

Describe the solution you'd like
When a backup fails for any reason, the user should be notified via email to let them know.

Describe alternatives you've considered
An Admin notice on the next login would also help the user to know they need to take steps to resolve the problem.

Additional context
Add any other context or screenshots about the feature request here.

[alanhagerman]

+1