title: adding gitlab-ci.yml variables break pipelines
body: <p>I have the following .gitlab-ci.yml configuration:</p>
  <pre><code>default:
      ...
  
  stages:
      - ...
  
  variables:
      # COLORS
      E: &quot;\e[1;91m&quot; # ERROR
      S: &quot;\e[1;32m&quot; # SUCCESS
      I: &quot;\e[1;34m&quot; # INFO
      R: &quot;\033[0m&quot; # RESET
      # Other vars
      ...
  
  .script-before: &amp;script-before
      - ...
  
  .other-script: &amp;other-script
  
  job_1:
      before_script:
          - *script-before
      stage: ...
      only:
          - ...
      variables:
          ...
      script:
          - *other-script
  </code></pre>
  <p>The pipelines don't run with these colors variables. I have tried changing the names of the variables but still the pipelines will not trigger.</p>