[NEW RULES] - Define author's responsibility when presentational roles conflict arises

[giacomo-petri]

New Rules:

• Check that elements with ARIA presentational role are not focusable
• Check that allowed child element of another element with presentational role does not cause presentational roles conflicts
• Check that elements with ARIA presentational role do not have global states or properties

Closes: #2193

Need for Call for Review: This will require a 2 weeks Call for Review

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