title: I cannot send email in Laradock environment
body: <p>So, I use <code>Laradock</code> for my PHP project development environment. I have issue when send email to mailtrap and have this error:</p>
  
  <p><code>sh: 1: /usr/sbin/sendmail: not found</code></p>
  
  <p>How to solve this? <strong>or is there any alternative to mail testing in Laradock the best practice and ways?</strong></p>
  
  <p>I already try to install sendmail in php-fpm dockerfile <code>apt-get install -y sendmail &amp;&amp; \</code>, and then re-build the container, seems the sendmail is installed as seen in the log, then restart the container, it still has same error:</p>
  
  <p><code>sh: 1: /usr/sbin/sendmail: not found</code></p>
  
  <p>my php-fpm/Dockerfile</p>
  
  <pre><code>...
  
  # always run apt update when start and after add new source list, then clean up at end.
  RUN set -xe; \
      apt-get install -y sendmail &amp;&amp; \
      apt-get update -yqq &amp;&amp; \
      pecl channel-update pecl.php.net &amp;&amp; \
      apt-get install -yqq \
        apt-utils \
        #
        #--------------------------------------------------------------------------
        # Mandatory Software's Installation
        #--------------------------------------------------------------------------
        #
        # Mandatory Software's such as ("mcrypt", "pdo_mysql", "libssl-dev", ....)
        # are installed on the base image 'laradock/php-fpm' image. If you want
        # to add more Software's or remove existing one, you need to edit the
        # base image (https://github.com/Laradock/php-fpm).
        #
        # next lines are here becase there is no auto build on dockerhub see https://github.com/laradock/laradock/pull/1903#issuecomment-463142846
        libzip-dev zip unzip &amp;&amp; \
        docker-php-ext-configure zip --with-libzip &amp;&amp; \
        # Install the zip extension
        docker-php-ext-install zip &amp;&amp; \
  
  
        php -m | grep -q 'zip'
  
  ...
  </code></pre>
  
  <p>I expect the mail sent to my mailtrap, It's once succeed when I used Wampserver</p>