message: Update the interface documentation of TINKAead.
  AEAD is "authenticated encryption with associated data".
  To keep compatibility, I didn't change the named parameter "additionalData". And to avoid confusion between the two terms, I left the documentation of the interface unchanged, but added a comment that explains why it is called "additionalData" here.
diff: NS_ASSUME_NONNULL_BEGIN
  /**
  - * The interface for authenticated encryption with additional authenticated data. Implementations of
  - * this interface are secure against adaptive chosen ciphertext attacks. Encryption with additional
  + * The interface for authenticated encryption with associated data. Implementations of
  + * this interface are secure against adaptive chosen ciphertext attacks. Encryption with associated
  * data ensures authenticity and integrity of that data, but not its secrecy. (see RFC 5116,
  * https://tools.ietf.org/html/rfc5116)
  + *
  + * The associated data is sometimes also called additional authenticated data,
  + * that's why the parameter in this interface is called additionalData.
  + *
  */
  @protocol TINKAead <NSObject>
  