UIAlertController.StyleAlert button duplicity wrinkle

I can't easily test UIAlertController.StyleAlert because each button has two accessible views with the same label:

```
Exception: MultipleElementsFoundException
Reason: Action 'Tap' was not performed because multiple UI elements matching ((respondsToSelector(isAccessibilityElement) && isAccessibilityElement) && accessibilityLabel("Download")) were found. Use grey_allOf(...) to create a more specific matcher.
Complete Error: Multiple elements were matched: (
"<_UIAlertControllerActionView:0x7f9df3435eb0; AX=Y; AX.label='Download'; AX.frame={{188, 352}, {134.5, 44}}; AX.activationPoint={255.25, 374}; AX.traits='UIAccessibilityTraitButton'; AX.focused='N'; frame={{0, 0}, {134.5, 44}}; opaque; alpha=1>",
""
). Please use selection matchers to narrow the selection down to single element.
```

It's easy to workaround the issue with grey_allOf, but this is a common case that should be handled by the framework in my opinion.