Changed logic to get customer subscriber status

Author: osrecio

app/code/Magento/Newsletter/Model/Subscriber.php

@@ -393,12 +393,14 @@ public function randomSequence($length = 32)
      */
     public function subscribe($email)
     {
-        $sendInformationEmail = false;
         $this->loadByEmail($email);
 
+        if ($this->getId() && $this->getStatus() == self::STATUS_SUBSCRIBED) {
+            return $this->getStatus();
+        }
+
         if (!$this->getId()) {
             $this->setSubscriberConfirmCode($this->randomSequence());
-            $sendInformationEmail = true;
         }
 
         $isConfirmNeed = $this->_scopeConfig->getValue(