> 50 bubble charts produce corrupt chart SVG

### Expected behaviour ###
All 51 bubbles should be displayed without error.

### Actual behaviour ###
The export server produces a corrupt SVG. When opening the file, following error is displayed:
```
error on line 44 at column 7087: Namespace prefix xlink for href on image is not defined
```
If I fix it by adding ` xmlns:xlink="http://www.w3.org/1999/xlink"` to the `svg` tag, the image is displayed without an error. But no bubbles are shown.

### Additional info ###
Base config structure used:
```json
{
"chart": {
"type": "bubble",
"plotBorderWidth": 1,
"zooming": {
"type": "xy"
}
},
"title": {
"text": "Highcharts Bubbles Sizing"
},
"subtitle": {
"text": "Smallest and largest bubbles are equal, intermediate bubbles different."
},
"xAxis": {
"gridLineWidth": 1
},
"yAxis": {
"startOnTick": false,
"endOnTick": false
},
"series": [
{
"data": [
[
5,
5,
5
]
],
"sizeBy": "area",
"name": "Size by area"
},
]
}
```
Command used:
```bash
highcharts-export-server --logToFile false --allowCodeExecution -nologo true -type=svg -outfile /tmp/out.svg -infile /tmp/in.json --logLevel 4
```

### Files used ###
[not_working.json](https://github.com/user-attachments/files/19227391/not_working.json)
[working.json](https://github.com/user-attachments/files/19227392/working.json)