docs: private String certificationRequestToPEM(PKCS10CertificationRequest csr) throws IOException {
          PemObject pemCSR = new PemObject("CERTIFICATE REQUEST", csr.getEncoded());
  
          StringWriter str = new StringWriter();
          JcaPEMWriter pemWriter = new JcaPEMWriter(str);
          pemWriter.writeObject(pemCSR);
          pemWriter.close();
          str.close();
          return str.toString();
      }