Article Index should be stored "in memory" for test cases

Author: mohsinh

src/test/java/org/springframework/data/elasticsearch/Article.java

@@ -14,7 +14,7 @@
 /**
  * Simple type to test facets
  */
-@Document(indexName = "articles", type = "article", shards = 1, replicas = 0, refreshInterval = "-1")
+@Document(indexName = "articles", type = "article", shards = 1, replicas = 0, refreshInterval = "-1", indexStoreType = "memory")
 public class Article {
 
     @Id