`path.iterdir()` yields `path` itself as the first item (with S3)

Given the following objects on S3: 

```
s3://my-bucket/my-directory/0.txt
s3://my-bucket/my-directory/1.txt
```

UPath("s3://my-bucket/my-directory").iterdir() yields: 

```
s3://my-bucket/my-directory
s3://my-bucket/my-directory/0.txt
s3://my-bucket/my-directory/1.txt
```

The first item is wrong, right? 