input: |
  TEST: **Custom title.**Testing

  TEST: **Custom title**.
  Testing
output: |-
  <div class="admonition test">
    <p class="admonition-title">
      Custom title
    </p>
    <p>
      Testing
    </p>
  </div>
  <div class="admonition test">
    <p class="admonition-title">
      Custom title
    </p>
    <p>
      .
  Testing
    </p>
  </div>
