recreating backendlistener context

Author: anthonygauthier

src/main/java/io/github/delirius325/jmeter/backendlistener/elasticsearch/ElasticsearchBackendClient.java

@@ -76,7 +76,7 @@ public Arguments getDefaultParameters() {
     @Override
     public void setupTest(BackendListenerContext context) throws Exception {
         try {
-            getDefaultParameters();
+            context = new BackendListenerContext(getDefaultParameters());
             this.filters = new HashSet<>();
             this.modes = new HashSet<>(Arrays.asList("info","debug","error","quiet"));
             this.bulkSize = Integer.parseInt(context.getParameter(ES_BULK_SIZE));