Analyze and fix VFS parallel test

[steve-s]

	@ParameterizedTest
	@MethodSource(VFS_DIRECTORIES_SOURCE)
	@Disabled // GR-61545
	public void parallelFsOperations(String vfsDir) throws ExecutionException, InterruptedException {
		int threadsCount = Runtime.getRuntime().availableProcessors();
		CountDownLatch latch = new CountDownLatch(threadsCount);
		ExecutorService executorService = Executors.newFixedThreadPool(threadsCount, new ThreadFactory() {

The test is ignored for the time being: https://github.com/search?q=repo%3Aoracle%2Fgraalpy-extensions%20parallelFsOperations&type=code