margin take in account only the first time

Nobody has claimed this yet.

Hi,

I'm stuck with a weird problem... I think it's a bug of the library.

I'm using jsBarcode to generate product labels
```html

TAG {{ product.tagNumber }}

PNR {{ product.material.uid }}

SER {{ product.serialNumber }}

```javascript
JsBarcode(document.getElementById("barcode1"))
.CODE128(`*RPO ${product.uid}*`, { height: 50, displayValue: false, margin: 0 })
.render();

JsBarcode(document.getElementById("barcode2"))
.CODE128(`*PNR ${product.material.uid}*`, { height: 50, displayValue: false, margin: 0 })
.render();

JsBarcode(document.getElementById("barcode3"))
.CODE128(`*SER ${product.serialNumber}*`, { height: 50, displayValue: false, margin: 0 })
.render();
```

Only the first generated barcode will have no margin
Other barcode will have default margin (10px)

If I switch the order, by example i generate the #barcode2 before the #barcode1, the #barcode2 will have no margin, and the 1 and 3 will have default margin...

Reproduce the issue using the three JsBarcode(...).CODE128(...).render() calls shown, with margin: 0 on each barcode. Inspect how the margin option is retained between successive renders; done means all three generated barcodes have no margin, regardless of call order.

Written by the indexing model from the issue text.