CBM man page examples should reflect latest changes for s3

cbbackupmgr config --help has examples like this:

When creating an archive in an object store such as S3 due care must be taken to ensure that the provided directory is empty and can be managed by cbbackupmgr.

$ cbbackupmgr config -a archive -r repo --s3 --s3-bucket 'bucket'

These are not valid options anymore - also examples should show how to supply the bucket name as per the changes - all man pages should be checked and updated