formatLanguageValue = ({ display_format, lang }) => {
  return display_format === "percent"
    ? `${lang.percent.toFixed(2).toString()} %`
    : lang.text;
}
Format language value.

@param {Object} args The function arguments.
@param {WakaTimeLang} args.lang The language object.
@param {"time" | "percent"} args.display_format The display format of the language node.
@returns {string} The formatted language value.