[Navigation] Add ariaLabelledBy prop

[mathildebuenerd]

Feature request summary

Add ariaLabelledBy prop that can be passed to Navigation component and added to the nav tag. They should contain the id of the navigation label.

Rationale

Currently it's not possible to pass a label to the Navigation component that can be used to differentiate this nav from other nav when navigating with landmarks.

We should be able to generate the following output (described here: https://www.w3.org/WAI/tutorials/menus/structure/#label-menus):

<nav aria-labelledby="mainmenulabel">
    <h2 id="mainmenulabel" class="visuallyhidden">Main Menu</h2>
</nav>

From this implementation:

<Navigation ariaLabelledBy="mainmenulabel">
    <VisuallyHidden>
        <h2 id="mainmenulabel">Main</h2>
    </VisuallyHidden>
</Navigation>

So that when navigating using landmarks there is an option "Main navigation".

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