[Fix] 0047063 UI: Rating – aria-label on input instead of label

[fhelfer]

Error: The “aria-label” attribute must not be used on any “label” element that is associated with a labelable element.
https://mantis.ilias.de/view.php?id=47063

Label with for= must not duplicate name via aria-label. Move
aria-label to the radio input; label remains for click target.
Apply to scale options and neutral option.

**PR Title:** `UI: Rating – aria-label am input statt am label`

**PR Description:**
```markdown
## Problem
- Validator: `<label for="..." aria-label="...">` ungültig, wenn das Label mit Formularelement verknüpft ist; Name soll aus Label-Inhalt kommen.

## Lösung
- aria-label vom label entfernt, auf das jeweilige input (radio) setzen.
- RatingInputTest anpassen.