use fs.rmdir recursive

[jimmywarting]

This... https://github.com/bcoe/c8/blob/a465b65d907b669714cfc3dca949efd667f499c3/bin/c8.js#L32 could possible be replaced by:

await fs.fsPromises.rmdir(argv.tempDirectory, { recursive: true })

if not now, then maybe in the feature when you decide to drop support for < 12.10

(only looking into all my sub dependencies seeing if there is anyway to reduce the total size)

[kaizhu256]

fs.rmdirSync is easier and less hassle (there's no reason it needs to be async in the [blocking] cli use-case). the same goes for the test-cases

fs.rmdirSync(argv.tempDirectory, { recursive: true });