fix(aria-allowed-attr): Add aria-orientation to radiogroup role

[Andarist]

We can read here that:

remain undefined on roles where an expected default orientation is ambiguous (e.g., radiogroup).

which, according to my understanding, implies that aria-orientation is allowed on radiogroup role, which would also make sense as visually we can present it either horizontally or vertically.

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[straker]

Yep, https://w3c.github.io/aria/#radiogroup shows aria-orientation is part of the inherited states and properties. Thanks for the pr.