Getting "EISDIR: illegal operation on a directory" when trying to delete a directory with ".delete()"

[rfermann]

Describe the bug
When calling .delete() on a Directory object, EISDIR: illegal operation on a directory, unlink '/your/directory/delete-me' is thrown.

Version: 13.0.3

To Reproduce

import { Project } from "ts-morph";

const project = new Project();

project.addDirectoryAtPath("./delete-me");
project.getDirectoryOrThrow("delete-me").delete();

project.saveSync();

Expected behavior
No error should be thrown. Instead the specified directory should get deleted.

Additional context
In @ts-morph/common unlink is called no matter if the target is a directory or a file. In case of directories rmdirshould be called instead.