esame-rabbitmq-client: restart the service on failures.

systemd/esame-rabbitmq-client.service

@@ -2,12 +2,20 @@
 Description=Esame - RabbitMQ client
 After=network-online.target
 Wants=network-online.target
+# Give up if restarted more than 10 times in 1 hour
+# TODO: systemd in CentOS 7 is too old for these params:
+StartLimitBurst=10
+StartLimitIntervalSec=3600
 
 [Service]
 Type=exec
 RemainAfterExit=yes
 EnvironmentFile=-/local/esame-machine.conf
 ExecStart=/usr/bin/python3 /usr/libexec/labmanager/rabbitmq-client.py
+# Possible values: on-failure, on-abnormal, on-abort, on-watchdog
+Restart=on-failure
+# Wait 30s before trying to restart the service
+RestartSec=30s
 
 [Install]
 WantedBy=esame.target esamekiosk.target esameshow.target graphical.target