docs: private static String getUPNStringFromSequence(final ASN1Sequence seq) {
          if (seq == null) {
              return null;
          }
          val id = ASN1ObjectIdentifier.getInstance(seq.getObjectAt(0));
          if (id != null && UPN_OBJECTID.equals(id.getId())) {
              val obj = (ASN1TaggedObject) seq.getObjectAt(1);
              val primitiveObj = obj.getObject();
  
              val func = FunctionUtils.doIf(Predicates.instanceOf(ASN1TaggedObject.class),
                  () -> ASN1TaggedObject.getInstance(primitiveObj).getObject(),
                  () -> primitiveObj);
              val prim = func.apply(primitiveObj);
  
              if (prim instanceof ASN1OctetString) {
                  return new String(((ASN1OctetString) prim).getOctets(), StandardCharsets.UTF_8);
              }
              if (prim instanceof ASN1String) {
                  return ((ASN1String) prim).getString();
              }
          }
          return null;
      }