title: remove a volume if exists
body: <p>As part of my CICD deployment, there is a volume <code>my_volume</code> that gets created on <code>docker-compose build/up</code>, that needs deleting every deployment.
  Therefore the CICID script calls <code>docker volume rm my_volume</code> before <code>docker-compose build/up</code>.
  But if a build fails, subsequent builds will error out on <code>docker volume rm my_volume</code>, because the volume doesn't exist.</p>
  <p>How can I remove this volume only if it exists?</p>