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
try {
            final int rounds = scaledRandomIntBetween(100, 10000);
            SearchRequest searchRequest = new SearchRequest().allowPartialSearchResults(true);
            SearchRequest scrollSearchRequest = new SearchRequest().allowPartialSearchResults(true)
                .scroll(new Scroll(TimeValue.timeValueMinutes(1)));
            for (int i = 0; i < rounds; i++) {
                try {
                    try {
                        PlainActionFuture<SearchPhaseResult> result = new PlainActionFuture<>();
                        final boolean useScroll = randomBoolean();
                        service.executeQueryPhase(
                            new ShardSearchRequest(
                                OriginalIndices.NONE,
                                useScroll ? scrollSearchRequest : searchRequest,
                                indexShard.shardId(),
                                0,
                                1,
                                AliasFilter.EMPTY,
                                1.0f,
                                -1,
                                null
                            ),
                            new SearchShardTask(123L, "", "", "", null, Collections.emptyMap()),
                            result
                        );
                        SearchPhaseResult searchPhaseResult = result.get();
                        List<Integer> intCursors = new ArrayList<>(1);
                        intCursors.add(0);
                        ShardFetchRequest req = new ShardFetchRequest(searchPhaseResult.getContextId(), intCursors, null);
                        PlainActionFuture<FetchSearchResult> listener = new PlainActionFuture<>();