Gets the list of distinguished names of the Certificate Authorities
that the server will accept certificates from. This will be set
during the TLS handshake if the server requests a certificate.
Otherwise, it will be
Each item in the list is a
GByteArray which contains the complete
subject DN of the certificate authority.
The list of
CA DNs. You should unref each element with
|The caller of the method takes ownership of the data, and is responsible for freeing it.|