[TEST] CCSDuelIT to not check successful shards (#75062)

CCSDuelIT sometimes fails due to an unexpected number of shards returned in the refresh response. We create an index with a certain number of shards and no replicas, and sometimes the number of shards refresh is higher by one than the shards we created. This is not symptom of a problem though, as we are checking that there are no failures, but rather indicates a relocation happening, during which both copies of the same shard have been refreshed.

Closes #61258
Closes #72637
Closes #67754

qa/multi-cluster-search/src/test/java/org/elasticsearch/search/CCSDuelIT.java

@@ -10,6 +10,7 @@
 
 import com.carrotsearch.randomizedtesting.RandomizedContext;
 import com.carrotsearch.randomizedtesting.annotations.TimeoutSuite;
+
 import org.apache.lucene.search.join.ScoreMode;
 import org.apache.lucene.util.TimeUnits;
 import org.elasticsearch.action.ActionListener;
@@ -74,6 +75,7 @@
 import org.elasticsearch.search.suggest.term.TermSuggestion;
 import org.elasticsearch.search.suggest.term.TermSuggestionBuilder;
 import org.elasticsearch.test.NotEqualMessageBuilder;
+import org.elasticsearch.test.hamcrest.ElasticsearchAssertions;
 import org.elasticsearch.test.rest.ESRestTestCase;
 import org.junit.AfterClass;
 import org.junit.Before;
@@ -206,8 +208,7 @@ public void afterBulk(long executionId, BulkRequest request, Throwable failure)
         assertTrue(bulkProcessor.awaitClose(30, TimeUnit.SECONDS));
 
         RefreshResponse refreshResponse = restHighLevelClient.indices().refresh(new RefreshRequest(INDEX_NAME), RequestOptions.DEFAULT);
-        assertEquals(0, refreshResponse.getFailedShards());
-        assertEquals(numShards, refreshResponse.getSuccessfulShards());
+        ElasticsearchAssertions.assertNoFailures(refreshResponse);
     }
 
     private static IndexRequest buildIndexRequest(String id, String type, String questionId) {