Fix tests for concurrent Search: TermsDocCountErrorIT

Signed-off-by: Wei Wang <[email protected]>

Author: Wei Wang

server/src/internalClusterTest/java/org/opensearch/search/aggregations/bucket/TermsDocCountErrorIT.java

@@ -225,6 +225,7 @@ public void setupSuiteScopeCluster() throws Exception {
         }
 
         indexRandom(true, builders);
+        indexRandomForMultipleSlices("idx");
         ensureSearchable();
     }
 

test/framework/src/main/java/org/opensearch/test/ParameterizedOpenSearchIntegTestCase.java

@@ -47,6 +47,7 @@ public void afterTests() {
         client().admin().cluster().prepareUpdateSettings().setPersistentSettings(settingsToUnset).get();
     }
 
+    // This method shouldn't be called in setupSuiteScopeCluster(). Only call this method inside single test.
     public void indexRandomForConcurrentSearch(String... indices) throws InterruptedException {
         if (dynamicSettings.get(CLUSTER_CONCURRENT_SEGMENT_SEARCH_SETTING.getKey()).equals("true")) {
             indexRandomForMultipleSlices(indices);