Deleting ps-backups leaves stale ".md5" file

[bezio]

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Whenever I delete some backup the finalizer/xbcloud performs the deletion within my s3-bucket (local minio-instance).
But the checksum file persists and therefore gets stale.

More about the problem

As said, when deleting backups there is still the checksum file on storage. It simply sits there and eats up space. When doing lots of backups (let's say an hourly backup, rotating over 24hrs and overwriting the different targets for a month you got 24 Backups - and about 720 .md5-Files. In my test-case I got 16kb each time so this alone is about 11MByte...)

Steps to reproduce

1. create a ps-backup
2. delete it after successful creation
3. check your s3-bucket to see the .md5-object still residing there

Versions

1. Kubernetes 1.27.11+k3s1
2. Operator 0.8.0
3. Database mysql-8.0.35 - xtrabackup-8.0.35

Anything else?

Is that an issue of the operator or of xtrabackups' xbcloud utility?