SearchServiceTests.testIsParallelCollectionSupportedForResults fails intermittently

```
12:37:10 org.elasticsearch.search.SearchServiceTests > testIsParallelCollectionSupportedForResults FAILED
12:37:10     java.lang.AssertionError
12:37:10         at __randomizedtesting.SeedInfo.seed([4140C168DE8FB0BB:771A78D5E4B36180]:0)
12:37:10         at org.junit.Assert.fail(Assert.java:86)
12:37:10         at org.junit.Assert.assertTrue(Assert.java:41)
12:37:10         at org.junit.Assert.assertFalse(Assert.java:64)
12:37:10         at org.junit.Assert.assertFalse(Assert.java:74)
12:37:10         at org.elasticsearch.search.SearchServiceTests.testIsParallelCollectionSupportedForResults(SearchServiceTests.java:2096)
```

```
./gradlew ':server:test' --tests "org.elasticsearch.search.SearchServiceTests.testIsParallelCollectionSupportedForResults" -Dtests.seed=4140C168DE8FB0BB -Dtests.locale=es-SV -Dtests.timezone=Africa/Banjul -Druntime.java=20
```
server/src/test/java/org/elasticsearch/search/SearchServiceTests.java
});
        CountDownLatch latch = new CountDownLatch(1);
        client().searchScroll(new SearchScrollRequest(scrollId), new ActionListener<>() {
            @Override
            public void onResponse(SearchResponse searchResponse) {
                try {
                    fail("Search not cancelled early");
                } finally {
                    latch.countDown();
                }
            }
            @Override
            public void onFailure(Exception e) {
                Throwable cancelledExc = e.getCause().getCause();
                assertThat(cancelledExc, is(instanceOf(TaskCancelledException.class)));
                assertThat(cancelledExc.getMessage(), is("task cancelled [simulated]"));
                assertThat(((TaskCancelledException) cancelledExc).status(), is(RestStatus.BAD_REQUEST));
                latch.countDown();
            }
        });
        latch.await();
        assertThat(searchContextCreated.get(), is(false));
        clearScrollRequest.setScrollIds(singletonList(scrollId));
        client().clearScroll(clearScrollRequest);
    }
    public void testWaitOnRefresh() {
        createIndex("index");
        final SearchService service = getInstanceFromNode(SearchService.class);
        final IndicesService indicesService = getInstanceFromNode(IndicesService.class);
        final IndexService indexService = indicesService.indexServiceSafe(resolveIndex("index"));