errors:

1. etcd stopped
2. crtl-C
bla etcd "ts"="2021-11-07 23:45:03.517326" "caller"={"file":"etcd.go","line":94} "msg"="campaign error" "error"="rpc error: code = Unavailable desc = error reading from server: EOF"
bla etcd "ts"="2021-11-07 23:45:03.518082" "caller"={"file":"loadbalancer.go","line":118} "level"=0 "msg"="stopping haproxy" "service"="haproxy"
bla etcd "ts"="2021-11-07 23:45:03.529380" "caller"={"file":"loadbalancer.go","line":123} "level"=0 "msg"="leading canceled" "id"="6a6c7cfc8dd69b62"
^Cbla main "ts"="2021-11-07 23:45:08.926006" "caller"={"file":"main.go","line":118} "level"=0 "msg"="haproxy-lb shutdown" "signal"="interrupt"
panic: send on closed channel

goroutine 1 [running]:
git.giftfish.de/ston1th/haproxy-lb/pkg/etcd.(*Cluster).Stop(0xc00017d340)
	git.giftfish.de/ston1th/haproxy-lb/pkg/etcd/etcd.go:213 +0x33
main.main()
	git.giftfish.de/ston1th/haproxy-lb/cmd/haproxy-lb/main.go:128 +0xebb