public Node withWantToFail(Agent agent, Instant at, String reason) {
        return with(status.withWantToFail(true))
                .with(history.with(new History.Event(History.Event.Type.wantToFail, agent, at, Optional.of(reason))));
    }
Returns a copy of this where wantToFail is set to true and history is updated to reflect this.
node-repository/src/main/java/com/yahoo/vespa/hosted/provision/Node.java