fix

mooctest-site-server/src/main/java/cn/iselab/mooctest/site/web/util/mongodb/MongoAPIUtils.java

@@ -11,7 +11,7 @@ import java.util.Map;
 public class MongoAPIUtils {
     public static final String MONGODB_HOST = "114.55.91.27";
     public static final String MONGODB_PORT = "80";
-    public static final String MONGODB_DB = "testGraph";
+    public static final String MONGODB_DB = "testdb";
     public static final String MONGODB_COLLECTION_REPORT= "report";
     public static final String MONGODB_COLLECTION_MUTATION = "mutation";
     public static final String MONGODB_COLLECTION_CASE_GRAPH = "caseGraph";