Add ExecReload to prometheus.service (#1131)

Author: BasixKOR

install/prometheus-install.sh

@@ -46,6 +46,7 @@ ExecStart=/usr/local/bin/prometheus \
     --config.file=/etc/prometheus/prometheus.yml \
     --storage.tsdb.path=/var/lib/prometheus/ \
     --web.listen-address=0.0.0.0:9090
+ExecReload=/bin/kill -HUP \$MAINPID
 
 [Install]
 WantedBy=multi-user.target" >$service_path