node-escpos prints twice

Nobody has claimed this yet.

I have the following code

```
const escpos = require('escpos');
escpos.USB = require('escpos-usb');
const device = new escpos.USB(2727, 772);
const options = { encoding: "ISO8859-15" /* default */ }
const printer = new escpos.Printer(device, options);
device.open(function(error){
console.log("internal call")
printer
.text("Test123 This is a happy printer doing it's job twice. Too happy?")
.close()
});
```

when I run the code with
`$node index.js`

the thermal printer will print the text twice. I have also tried to add the `cut()` `flush()` method within the open callback method. I can see that this callback method is called two times, as in the console it prints "internal call" twice.

Expected: the printer only prints the text once.

Thanks for the help

Start with index.js and the device.open callback shown in the report, then run node index.js while observing the callback log and printer output. Trace why the callback is entered twice and verify that the callback and text are each processed only once.

Written by the indexing model from the issue text.