🐛 Bug Report

I've created excel files using OpenPyXL and now want to modify these using ExcelJS. However, there are no sheets on the Workbook.worksheets array.
There was a single worksheet located at Workbook._worksheets on the undefined property, but the others were missing.

I did some debugging, and found that the issue occurs at xlsx.js::353, this.workbook.model = model. The model properly loads and contains all the worksheets, but the setter doesn't handle them correctly.

In workbook.js::200, const {id, name, state} = worksheetModel; has id undefined, so at some point the worksheet id is missing or not set properly. This may be caused by OpenPyXL not saving the worksheet properly?

Lib version: 3.8.2
Openpyxl: 3.0.3

Steps To Reproduce

Python

    wb = Workbook()
    example_row = ['1', '2', '3']
    ka_list = wb.create_sheet('KA lijst')
    ka_list.append(example_row)
    wb.save(f"output/example.xlsx")

JS

    workbook = new Workbook();
    await workbook.xlsx.readFile(__dirname + 'output/example.xlsx');
    const kaWorksheet = workbook.getWorksheet('KA lijst');
    // kaWorksheet is undefined

File with the incorrect behaviour:
lasschema.xlsx

The expected behaviour:

I would expect to be able to retrieve the specific sheet using getWorksheet('KA') and be able to read its rows.

Potential fix:

In workbook-xform.js::160 we find the worksheet using rel.Target. ( worksheet = model.worksheetHash[xl/${rel.Target}])
For the given file, rel.Target is "/xl/worksheets/sheet1.xml", including a '/xl/' already. The lookup with xl/xl/worksheets/sheet1.xml therefore won't find it.

For example

  if (rel.Target.startsWith('/xl/')) {
    rel.Target = rel.Target.substr(4);
  }

We could slice the "/xl"section off rel.Target when it's present to fix it.