Form breaks with "Error rendering widget (tagger):

When attempting to edit some of the demo collections in EOEPCA STAC (https://eoapi.apx.develop.eoepca.org/manager/collections/sentinel-2-iceland/edit), the form crashes with:

```
WidgetTagger: 'items.allowOther.type' is required for the 'tagger' widget with 'enum' options. Use the 'select' widget instead.
@.item_assets.2.roles
{
"label": "Roles",
"type": "array",
"ui:widget": "tagger",
"items": {
"label": "Role",
"type": "string",
"enum": [
[
"thumbnail",
"Thumbnail"
],
[
"overview",
"Overview"
],
[
"data",
"Data"
],
[
"metadata",
"Metadata"
]
]
}
}

```

is this an issue with the data and / or can STAC Manager be more robust against this?