Tweak react-a11y-anchors to ignore href="#" if onClick is present

[cdeutsch]

I don't think this part of react-a11y-anchors is a valid rule...

`Enforce an anchor element's href prop value is not just #
http://webaim.org/techniques/hypertext/#keyboard

...at least not if onClick is present

From the article...

<a href="#" onmouseover="dropdownmenu()">Products</a>

Both keyboard users and mouse users will experience nothing at all when attempting to activate the link.

If onmouseover was onclick then this statement is false because the click would do something.

Using <a href="#" onClick="foo()"> to trigger Javascript onClick is a very common pattern.

[JoshuaKGoldberg]

💀 It's time! 💀

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👋 It was a pleasure open sourcing with you!