code: public function execute(\Magento\Framework\Event\Observer $observer) // @codingStandardsIgnoreLine - unused parameter
      {
          if ($this->config->getType() == Config::FASTLY && $this->config->isEnabled()) {
              $this->purgeCache->sendPurgeRequest();
          }
      }
docs: Flush Fastly CDN cache
  
  @param \Magento\Framework\Event\Observer $observer
  @throws \Zend_Uri_Exception