Fix create_index/create_index_with_IOException issue caused by OpenSe…

…arch PR change (opensearch-project#1899)

* Added setDefaultMediaType for create_index and create_index_with_IOException

Signed-off-by: Mitchell Gale <[email protected]>
(cherry picked from commit 7b932a7)
Signed-off-by: Mitchell Gale <[email protected]>

opensearch/src/test/java/org/opensearch/sql/opensearch/client/OpenSearchRestClientTest.java

@@ -19,6 +19,7 @@
 import static org.mockito.Mockito.never;
 import static org.mockito.Mockito.verify;
 import static org.mockito.Mockito.when;
+import static org.opensearch.core.xcontent.MediaTypeParserRegistry.setDefaultMediaType;
 import static org.opensearch.sql.opensearch.client.OpenSearchClient.META_CLUSTER_NAME;
 import static org.opensearch.sql.opensearch.data.type.OpenSearchDataType.MappingType;
 
@@ -34,6 +35,7 @@
 import lombok.SneakyThrows;
 import org.apache.commons.lang3.reflect.FieldUtils;
 import org.apache.lucene.search.TotalHits;
+import org.junit.jupiter.api.BeforeAll;
 import org.junit.jupiter.api.BeforeEach;
 import org.junit.jupiter.api.DisplayNameGeneration;
 import org.junit.jupiter.api.DisplayNameGenerator;
@@ -101,6 +103,11 @@ void setUp() {
     client = new OpenSearchRestClient(restClient);
   }
 
+  @BeforeAll
+  static void setUpJSON() {
+    setDefaultMediaType(XContentType.JSON);
+  }
+
   @Test
   void is_index_exist() throws IOException {
     when(restClient.indices()