label: should check ariaLabelledByElements as well

### Product

axe-core

### Product Version

4.10.3

### Latest Version

- [x] I have tested the issue with the latest version of the product

### Issue Description

#### Expectation
Get `ariaLabelledByElements` value if possible for label value as well.

#### Actual
Only get `aria-labelledby` attribute, and don't parse `ariaLabelledByElements` value.

#### How to Reproduce
```html

Test label

```
```javascript
document.querySelector('input').ariaLabelledByElements = [document.querySelector('p')];
```

#### Additional context
When using custom element with shadow dom, it's the only way to refer to outer element.