deriveLabelForUISchemaElement() return undefined if no translation was found and no label defined

### Describe the bug

While working on https://github.com/eclipsesource/jsonforms/pull/2270#pullrequestreview-1884750920, it was discovered that the translation was not working properly.

In the example https://deploy-preview-2270--jsonforms-examples.netlify.app/vue-vanilla/#categorization the second tab "address" is empty. In uischema there is only an "i18n" key defined and no label.

```json
"type": "Category",
"i18n": "address",
"elements": []
```

### Expected behavior

the expected behavior is that at least the key "address" will be returned, even if it cannot be translated.

### Steps to reproduce the issue

1. Go to https://deploy-preview-2270--jsonforms-examples.netlify.app/vue-vanilla/#categorization
2. second tab is empty, but should be labeled with "address"

### Screenshots

_No response_

### Which Version of JSON Forms are you using?

v3.2.1

### Framework

Vue

### RendererSet

Vanilla

### Additional context

_No response_