@Test
    void testAsyncExecution() {
        Chain<Searcher> chain = new Chain<>(new FirstSearcher(), new SecondSearcher());
        Execution execution = new Execution(chain, Execution.Context.createContextStub());
        Query query = new Query();
        execution.search(query);
    }
Tests async execution of search chains.

@author Peter Thomas
@author bratseth
container-search/src/test/java/com/yahoo/search/searchchain/VespaAsyncSearcherTest.java