@Override
    public boolean test(Node node) {
        return states.contains(node.state()) && filter.test(node);
    }
A filter for nodes, matching by state. This should be the top-most filter so that the node-repository can determine
which node states to read before testing additional filters.

@author mpolden
node-repository/src/main/java/com/yahoo/vespa/hosted/provision/node/filter/NodeFilter.java