title: Bitbucket pipline deploy with rsync - Host key verification failed
body: <p>I have created a bitbucket pipeline under a repository and i have generated the SSH Keys and have updated the authorized_keys file in the host. Delivery part is carried by rsync, during the deployment phase i'm getting the following error.</p>
  
  <pre><code>rsync -zrSlh --stats --exclude-from=deployment-exclude-list.txt $BITBUCKET_CLONE_DIR/ $DEPLOY_USER@$DEPLOY_HOST:$DEPLOY_PATH;
  Host key verification failed.
  rsync: connection unexpectedly closed (0 bytes received so far) [sender]
  rsync error: unexplained error (code 255) at io.c(235) [sender=3.1.2]
  </code></pre>
  
  <p>My bitbucket-pipelines.yml as follows,</p>
  
  <pre><code>image: php:7.2.1-fpm
  
  pipelines:
    default:
      - step:
          caches:
            - composer
          script:
            - apt-get update
            - apt-get install git -y
            - export APP_ENV=testing
            - curl -sS https://getcomposer.org/installer | php -- --install-dir=/usr/local/bin --filename=composer
            - composer install
      - step:
              name: Deploy to test
              deployment: test
              script:
                - apt-get update
                - apt-get install ssh -y
                - apt-get install rsync -y
                - rsync -zrSlh --stats --exclude-from=deployment-exclude-list.txt $BITBUCKET_CLONE_DIR/ $DEPLOY_USER@$DEPLOY_HOST:$DEPLOY_PATH;
  </code></pre>
  
  <p>According to the documentation this yml should work, but i'm getting above error, your help is really appreciated and welcome.</p>