apcupsd `offbattery` script

[RemingtonRohel]

This script restarts the restart_borealis.service system service. At our sites with two radar computers, this could mean two radars both attempting to run the radar after a power outage (only when the outage is short, so the computers don't reboot, only go on and off UPS power). We should modify the offbattery script to use systemctl is-enabled restart_borealis.service and only restart the service if it is enabled, ensuring that only one computer runs the radar after these events.

[RemingtonRohel]

The onbattery script handles the logic of ensuring only one computer runs the radar after power is restored, so this issue is moot.