pub fn issue_client_cert(
ca: &mut CertificateAuthority,
common_name: impl Into<String>,
email: Option<String>,
validity_days: u32,
) -> Result<IssuedCertificate>pub fn issue_client_cert(
ca: &mut CertificateAuthority,
common_name: impl Into<String>,
email: Option<String>,
validity_days: u32,
) -> Result<IssuedCertificate>