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
searchRequest,
            indexShard.shardId(),
            0,
            1,
            AliasFilter.EMPTY,
            1.0f,
            -1,
            null
        );
        try (
            ReaderContext reader = createReaderContext(indexService, indexShard);
            SearchContext context = service.createContext(reader, request, mock(SearchShardTask.class), ResultsType.NONE, randomBoolean())
        ) {
            assertNotNull(context);
        }
        searchSourceBuilder.docValueField("unmapped_field");
        try (
            ReaderContext reader = createReaderContext(indexService, indexShard);
            SearchContext context = service.createContext(reader, request, mock(SearchShardTask.class), ResultsType.NONE, randomBoolean())
        ) {
            assertNotNull(context);
        }
        searchSourceBuilder.docValueField("field2");
        try (ReaderContext reader = createReaderContext(indexService, indexShard)) {
            IllegalArgumentException ex = expectThrows(
                IllegalArgumentException.class,
                () -> service.createContext(reader, request, mock(SearchShardTask.class), ResultsType.NONE, randomBoolean())
            );
            assertEquals(
                "Trying to retrieve too many docvalue_fields. Must be less than or equal to: [1] but was [2]. "