public Node withParentHostname(String parentHostname) {
        return new Node(id, extraId, ipConfig, hostname, Optional.of(parentHostname), flavor, status, state, allocation,
                        history, type, reports, modelName, reservedTo, exclusiveToApplicationId, provisionedForApplicationId, hostTTL, hostEmptyAt,
                        exclusiveToClusterType, switchHostname, trustStoreItems, cloudAccount, wireguardPubKey);
    }
Returns a copy of this node with the parent hostname assigned to the given value.
node-repository/src/main/java/com/yahoo/vespa/hosted/provision/Node.java