Perform Yii2 application reset before performing request in functional tests (#4651)

* Reset Yii2 application before perform request

* Reverting previous solution and replacing it with recreated Yii2 Request object

* Recreating Yii2 request object with original component's configuration

Author: erickskrauch

src/Codeception/Lib/Connector/Yii2.php

@@ -135,6 +135,8 @@ public function doRequest($request)
 
         ob_start();
 
+        // recreating request object to reset headers and cookies collections
+        $app->set('request', $app->getComponents()['request']);
         $yiiRequest = $app->getRequest();
         if ($request->getContent() !== null) {
             $yiiRequest->setRawBody($request->getContent());