Before this ships, can we rename fs.s3a.server-side-encryption-key to fs.s3a.server-side-encryption.key.
This makes it consistent with all other .key secrets in S3A. so
- simplifies documentation
- reduces confusion "is it a - or a ."? This confusion is going to surface in config and support
I know that CDH is shipping with the old key, but it'll be easy for them to add a deprecation property to handle the migration. I do at least what the ASF release to be stable before it ships.