Update 'Makefile'

remove group, systemd not always happy about it.

Makefile

@@ -65,7 +65,6 @@ systemd-service:
 	[Service]
 	Type=simple
 	User=nobody
-	Group=nogroup
 	ExecStart=/usr/local/bin/$(BINARY_NAME)
 	Restart=always
 	RestartSec=10