description: An optional list of hex-encoded SHA-256 hashes
                            of the authorized client certificates.
                          items:
                            type: string
                          type: array
                        verifyCertificateSpki:
                          description: An optional list of base64-encoded SHA-256

*   Added **categorical data** processing layers:
    *   `IntegerLookup` & `StringLookup`: build an index of categorical feature
        values
    *   `CategoryEncoding`: turn integer-encoded categories into one-hot,
        multi-hot, or tf-idf encoded representations
    *   `CategoryCrossing`: create new categorical features representing
        co-occurrences of previous categorical feature values

  - `status.conditions` may not contain duplicate types
  - `status.conditions[*].status` is now required
  - `status.certificate` must be PEM-encoded, and contain only CERTIFICATE blocks ([#91685](https://github.com/kubernetes/kubernetes/pull/91685), [@liggitt](https://github.com/liggitt)) [SIG API Machinery, Architecture, Auth, CLI and Testing]