Error: Missing key/value separator

╷
│ Error: Missing key/value separator
│
│   on main.tf line 168, in resource "helm_release" "grafana":
│  168:     value = {"example.com"}
│
│ Expected an equals sign ("=") to mark the beginning of the attribute value.
╵

resource "helm_release" "grafana" {
 name             = "grafana"
 create_namespace = true
 namespace        = "grafana"
 repository       = "https://grafana.github.io/helm-charts"
 chart            = "grafana"

 set {
   name  = "ingress.enabled"
   value = "true"
 }
 set_list {
   name  = "ingress.hosts"
   value = ["example.com"]
 }
 set {
   name  = "ingress.ingressClassName"
   value = "nginx"
 }
 set {
   name  = "ingress.tls"
   value = "true"
 }
}