Auto merge of #25576 - pshaughn:menuelement, r=jdm

Implement HTMLMenuElement

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Per spec, "The menu element is simply a semantic alternative to ul to express an unordered list of commands (a "toolbar")." We already have the CSS for it in user-agent.css, and this gives us the interface object.

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- [X] These changes fix #24990

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- [X] There are tests for these changes

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components/script/dom/customelementregistry.rs

@@ -1145,6 +1145,7 @@ fn is_extendable_element_interface(element: &str) -> bool {
         element == "map" ||
         element == "mark" ||
         element == "marquee" ||
+        element == "menu" ||
         element == "meta" ||
         element == "meter" ||
         element == "nav" ||