test: cover 'close' method in Dir class

cover 'close' method (in Dir class) with tests
Add 2 tests for full covering of method 'close' in class Dir
1. If pass smth that not string as a callback - throw an exception
2. If do .close() on already closed directory - throw an exception

PR-URL: https://github.com/nodejs/node/pull/30310


Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Anna Henningsen <anna@addaleax.net>
Reviewed-By: Jeremiah Senkpiel <fishrock123@rocketmail.com>
Reviewed-By: Luigi Pinca <luigipinca@gmail.com>
Reviewed-By: Gireesh Punathil <gpunathi@in.ibm.com>
Reviewed-By: Ruben Bridgewater <ruben@bridgewater.de>
Reviewed-By: Trivikram Kamat <trivikr.dev@gmail.com>