delete markers cause ghost folders when listing versioned bucket

Issue description

s3contents doesn't seem to handle ListObjectsV2 action properly with versioned buckets as it displays all prefixes without making sure if they are delete marker or actual "folders".

Steps to reproduce

activate versioning on a bucket
create a folder
delete (or rename) the folder
refresh jupyterlab
the supposed-to-be-deleted folder will still show up in the filesystem, but will be unopenable & will have a Last Modified date of 52 years ago. Any action on the folder (like opening) will return a Folder not found as expected by s3.

Fix hints

(currently working on this, hope to have a PR coming in a few days)

Note: in Minio the versioning is unavailable in a single-disk setup, and requires to deploy in Distributed Mode to use it.

The ListBucketResult returning a KeyCount of 0 might be enough to indicate that the folder is a delete marker and hide it in the filesystem?

<ListBucketResult xmlns="http://s3.amazonaws.com/doc/2006-03-01/">
   <Name>mybucket</Name>
   <Prefix>myprefix/test/</Prefix>
   <KeyCount>0</KeyCount>
   <MaxKeys>1</MaxKeys>
   <Delimiter>/</Delimiter>
   <IsTruncated>false</IsTruncated>
   <EncodingType>url</EncodingType>
</ListBucketResult>

danielfrg / s3contents