Correctly apply current-menu-ancestor class in Nav block

[getdave]

What?

Applies the current-menu-ancestor class to the <li> not the <a>

Closes https://github.com/WordPress/gutenberg/issues/50069

Why?

Consistency with current-menu-item which is applied to the <li>.

How?

Applies the current-menu-ancestor class to the <li> not the <a>

Testing Instructions

• Create Navigation menu
• Add a Page
• Add a submenu under that page and add some links.
• Save
• View front of site
• Inspect HTML of top level link
• See class is on li not a.

Testing Instructions for Keyboard

Screenshots or screencast

[getdave]

I'm guessing this class isn't applied in the Editor because there is no concept of this there right?

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[MaggieCabrera]

I'm guessing this class isn't applied in the Editor because there is no concept of this there right?

that sounds about right, it would be hard to map

[MaggieCabrera]

I'm ok tentatively approving this if we get some more feedback from themers. If this only affect block themes, I've done a search on a dump I have of block themes in the themes repo and I don't see many themes that would be affected by this change