code: func (c *CertAuthorityV2) TLSCA() (*tlsca.CertAuthority, error) {
  	if len(c.Spec.TLSKeyPairs) == 0 {
  		return nil, trace.BadParameter("no TLS key pairs found for certificate authority")
  	}
  	return tlsca.New(c.Spec.TLSKeyPairs[0].Cert, c.Spec.TLSKeyPairs[0].Key)
  }
docs: // TLSCA returns TLS certificate authority