doc: Add resticprofile to scheduling section

doc/040_backup.rst

@@ -533,8 +533,11 @@ Restic does not have a built-in way of scheduling backups, as it's a tool
 that runs when executed rather than a daemon. There are plenty of different
 ways to schedule backup runs on various different platforms, e.g. systemd
 and cron on Linux/BSD and Task Scheduler in Windows, depending on one's
-needs and requirements. When scheduling restic to run recurringly, please
-make sure to detect already running instances before starting the backup.
+needs and requirements. If you don't want to implement your own scheduling,
+you can use `resticprofile <https://github.com/creativeprojects/resticprofile/#resticprofile>`__.
+
+When scheduling restic to run recurringly, please make sure to detect already
+running instances before starting the backup.
 
 Space requirements
 ******************