title: Modifying docker image to work with gitlab-ci
body: <p>I have a gitlab pages site that is built inside a docker container. I found a base image that contains 95% of what I want. With my old ci, I was installing extra packages before the build step. I want to create a new image with these packages installed, and use that image. I was able to build and run this image, but it no longer runs in gitlab actions. I'm not sure why.</p>
  <ul>
  <li>Git repo: <a href="https://gitlab.com/hybras/hybras.gitlab.io" rel="nofollow noreferrer">https://gitlab.com/hybras/hybras.gitlab.io</a></li>
  <li>CI Config:</li>
  </ul>
  <pre class="lang-yaml prettyprint-override"><code>image: klakegg/hugo:asciidoctor-ci # old
  image: registry.gitlab.com/hybras/hybras.gitlab.io # new
  
  variables:
    GIT_SUBMODULE_STRATEGY: recursive
    SSHPASS: $SSHPASS
  
  pages:
    script:
    - gem install asciidoctor-html5s # remove these package installs in the new version
    - apk add openssh sshpass # remove these package installs in the new version
    - hugo
    - sshpass -p $SSHPASS scp -r public/* $HOST_AND_DIR
    artifacts:
      paths:
      - public
    only:
    - master
  
  </code></pre>
  <ul>
  <li>Successful Job: Installs the packages, builds the site, scp's it to my mirror</li>
  <li>Dockerfile:</li>
  </ul>
  <pre><code>FROM klakegg/hugo:asciidoctor
  
  RUN gem install asciidoctor-html5s --no-document \
      &amp;&amp; apk --no-cache add openssh sshpass
  CMD hugo 
  </code></pre>
  <ul>
  <li>Failed CI Run: <code>Error: unknown command &quot;sh&quot; for &quot;hugo&quot;</code></li>
  </ul>