title: Use CI_COMMIT_BRANCH branch name as a file path
body: <p>I'm trying to setup a pipeline where the output will be written to a location based on the branch on which the pipeline was triggered.</p>
  <p>Example: If branch was <code>topic/124579</code>,
  then output must be written to <code>D:/Artifacts/topic/124579</code>.</p>
  <p>But when I use this on my <code>.gitlab-ci.yml</code>, the runner creates a directory with the name <code>CI_COMMIT_BRANCH</code> literally: <code>D:/Artifacts/CI_COMMIT_BRANCH</code>.</p>
  <p>Here are a few things that I've tried</p>
  <p><code>md D:/Artifacts/CI_COMMIT_BRANCH</code> results in <code>D:/Artifacts/CI_COMMIT_BRANCH</code> as before</p>
  <p><code>md D:/Artifacts/$CI_COMMIT_BRANCH</code> results in <code>D:/Artifacts/$CI_COMMIT_BRANCH</code></p>
  <p><code>md D:/Artifacts/&quot;$CI_COMMIT_BRANCH&quot;</code> also results in <code>D:/Artifacts/$CI_COMMIT_BRANCH</code></p>
  <p>How do I do this ?</p>
  <p>I'm running my jobs on a self-hosted Windows runner, using <code>cmd</code> as the shell.</p>