expandDirectories doesn't work with `**`

[arcanis]

Runkit

const fs = require(`fs`);
const globby = require(`globby`);

fs.mkdirSync(`foo`);
fs.writeFileSync(`foo/bar.ts`, ``);

// Works -> ["foo/bar.ts"]
console.log(globby.sync(`foo`));

// Doesn't work -> []
console.log(globby.sync(`**/foo`));