Adopt core that `_flush` and `_force_merge` doesn't refresh anymore (elastic/x-pack-elasticsearch#2752)

Relates to elastic/elasticsearch#27000

Original commit: elastic/x-pack-elasticsearch@52e9951094

plugin/src/test/java/org/elasticsearch/xpack/graph/test/GraphTests.java

@@ -101,6 +101,7 @@ public class GraphTests extends XPackSingleNodeTestCase {
         // issue https://github.com/elastic/x-pack-elasticsearch/issues/918
         ForceMergeResponse actionGet = client().admin().indices().prepareForceMerge("test").setFlush(true).setMaxNumSegments(1)
                 .execute().actionGet();
+        client().admin().indices().prepareRefresh("test").get();
         assertAllSuccessful(actionGet);
         for (IndexShardSegments seg : client().admin().indices().prepareSegments().get().getIndices().get("test")) {
             ShardSegments[] shards = seg.getShards();

plugin/src/test/java/org/elasticsearch/xpack/watcher/test/integration/HistoryIntegrationTests.java

@@ -99,7 +99,7 @@ public class HistoryIntegrationTests extends AbstractWatcherIntegrationTestCase
         ensureWatcherStarted();
         watcherClient().prepareExecuteWatch("test_watch").setRecordExecution(true).get();
 
-        flush(".watcher-history*");
+        refresh(".watcher-history*");
         SearchResponse searchResponse = client().prepareSearch(".watcher-history*").setSize(0).get();
         assertHitCount(searchResponse, 1);
 
@@ -137,7 +137,7 @@ public class HistoryIntegrationTests extends AbstractWatcherIntegrationTestCase
 
         watcherClient().prepareExecuteWatch("test_watch").setRecordExecution(true).get();
 
-        flush(".watcher-history*");
+        refresh(".watcher-history*");
         SearchResponse searchResponse = client().prepareSearch(".watcher-history*").setSize(0).get();
         assertHitCount(searchResponse, 1);
 

qa/rolling-upgrade/src/test/resources/rest-api-spec/test/mixed_cluster/10_basic.yml

@@ -53,7 +53,7 @@ setup:
        body: {"f1": "v8_mixed", "f2": 12}
 
  - do:
-     indices.flush:
+     indices.refresh:
         index: test_index
 
  - do:
@@ -81,7 +81,7 @@ setup:
        id: d12
 
  - do:
-     indices.flush:
+     indices.refresh:
         index: test_index
 
 ---

qa/rolling-upgrade/src/test/resources/rest-api-spec/test/old_cluster/10_basic.yml

@@ -24,10 +24,6 @@
           - '{"index": {"_index": "test_index", "_type": "test_type"}}'
           - '{"f1": "v5_old", "f2": 4}'
 
- - do:
-     indices.flush:
-        index: test_index
-
  - do:
      search:
         index: test_index

qa/rolling-upgrade/src/test/resources/rest-api-spec/test/old_cluster/50_token_auth.yml

@@ -65,12 +65,6 @@
           - '{"index": {"_index": "token_index", "_type": "doc", "_id" : "5"}}'
           - '{"f1": "v5_old", "f2": 4}'
 
-  - do:
-      headers:
-        Authorization: Bearer ${token}
-      indices.flush:
-        index: token_index
-
   - do:
       headers:
         Authorization: Bearer ${token}

qa/rolling-upgrade/src/test/resources/rest-api-spec/test/upgraded_cluster/10_basic.yml

@@ -29,10 +29,6 @@
           - '{"index": {"_index": "test_index", "_type": "test_type"}}'
           - '{"f1": "v5_upgraded", "f2": 14}'
 
- - do:
-     indices.flush:
-        index: test_index
-
  - do:
      search:
         index: test_index