private static WordItem getFirstWord(Result result) {
        var resultRoot = (AndItem) result.getQuery().getModel().getQueryTree().getRoot();
        return (WordItem) resultRoot.getItem(0);
    }
Tests significance term in the search chain.

@author MariusArhaug
container-search/src/test/java/com/yahoo/search/significance/test/SignificanceSearcherTest.java