Dropdown editor does not respect delimiter option #1792

Hi 👋

TL;DR; demo

It looks like the dropdown editor in Jspreadsheet CE does not support or properly handle the delimiter option.

When using a dropdown column with multiple selection enabled, changing the delimiter parameter does not affect the resulting cell value. The value is still joined using the default delimiter instead of the one provided in the configuration.

Expected behavior:

When setting a custom delimiter in the column configuration, the selected values should be joined using that delimiter.

Actual behavior:

The delimiter option has no effect. The resulting value always uses the default delimiter.

Example configuration:

{
    type: 'dropdown',
    multiple: true,
    delimiter: '|',
    source: ['A', 'B', 'C']
}

Selecting A and B still results in:

A,B

Instead of:

A|B

Jspreadsheet CE version: 5.0.4
Is this expected behavior, or is it a bug?

Thanks!