enable withCredentials in elasticsearch basic auth

src/app/services/elasticsearch/es-datasource.js

@@ -37,6 +37,7 @@ function (angular, _, config, kbn, moment) {
       };
 
       if (this.basicAuth) {
+        options.withCredentials = true;
         options.headers = {
           "Authorization": "Basic " + this.basicAuth
         };