Found the solution myself.
This is a complete config.
> resource "hcloud_load_balancer_service" "web_lb_service" {
> load_balancer_id = hcloud_load_balancer.web_lb.id
> protocol = "https"
> listen_port = var.https_port
> destination_port = var.https_port
> health_check {
> protocol = "http"
> port = "443"
> interval = "10"
> timeout = "10"
> http {
> path = "/"
> status_codes = ["2??", "3??"]
> }
> }
> http {
> certificates = [data.hcloud_certificate.lb_cert.id]
> }
> }