fixed umd test issue

Author: fayyazarshad

packages/optimizely-sdk/lib/core/audience_evaluator/index.js

@@ -33,7 +33,7 @@ var MODULE_NAME = 'AUDIENCE_EVALUATOR';
  *                                                   Optimizely evaluators cannot be overridden.
  * @constructor
  */
-export var AudienceEvaluator = function AudienceEvaluator(UNSTABLE_conditionEvaluators) {
+export function AudienceEvaluator(UNSTABLE_conditionEvaluators) {
   this.typeToEvaluatorMap = fns.assign({}, UNSTABLE_conditionEvaluators, {
     custom_attribute: customAttributeConditionEvaluator,
   });