src/language-markdown/printer-markdown.js/alignListPrefix
function alignListPrefix(prefix, options) {
  const additionalSpaces = getAdditionalSpaces();
  return (
    prefix +
    " ".repeat(
      additionalSpaces >= 4 ? 0 : additionalSpaces // 4+ will cause indented code block
    )
  );

  function getAdditionalSpaces() {
    const restSpaces = prefix.length % options.tabWidth;
    return restSpaces === 0 ? 0 : options.tabWidth - restSpaces;
  }
}