S3 backup to an ObjectBucket: MultipartUpload: upload multipart failed

Issue

• RHACS only offer bucket to GCP or AWS buckets. Configuring Amazon S3 to backup to an ObjectBucket provisioned on ODF seems to be partially possible.
• The test works but during the backup, zip files get uploaded multiple times into the bucket and an error is displayed in central logs about failing multiPart upload

externalbackups/plugins/s3: 2022/07/21 09:35:33.947612 s3.go:155: Info: Starting S3 Backup
externalbackups/plugins/s3: 2022/07/21 09:35:33.939710 s3.go:155: Info: Starting S3 Backup
externalbackups/plugins/s3: 2022/07/21 09:36:46.883587 s3.go:169: Info: Successfully backed up to S3
externalbackups/scheduler: 2022/07/21 09:36:46.893106 schedule.go:98: Info: Successfully ran backup to *s3.s3
externalbackups/plugins/s3: 2022/07/21 09:36:46.946610 s3.go:169: Info: Successfully backed up to S3
externalbackups/scheduler: 2022/07/21 09:36:46.950463 schedule.go:98: Info: Successfully ran backup to *s3.s3
...
externalbackups/plugins/s3: 2022/07/21 09:36:50.679285 s3.go:204: Error: S3 backup error: MultipartUpload: upload multipart failed
    upload id: xxxdf10105d0000xxxxx
caused by: InternalError: We encountered an internal error. Please try again.
    status code: 500, request id: xxx-xxx-zzz, host id: xxxx-sss-zzz
externalbackups/scheduler: 2022/07/21 09:36:50.679363 schedule.go:105: Error: failed to send backup to *s3.s3: error creating backup in bucket "s3-openshift-storage" with key "rhacs-backup-zzz-xxxx-xxx-xxxx/backup_2022-07-21T09:35:33.zip" (code: MultipartUpload; message: upload multipart failed)