src/language-js/printer-estree.js/isIndentableBlockComment
function isIndentableBlockComment(comment) {
  // If the comment has multiple lines and every line starts with a star
  // we can fix the indentation of each line. The stars in the `/*` and
  // `*/` delimiters are not included in the comment value, so add them
  // back first.
  const lines = `*${comment.value}*`.split("\n");
  return lines.length > 1 && lines.every((line) => line.trim()[0] === "*");
}