HTMLExecutingFunctionsSniff: Add more unsafe functions to $HTMLExecutingFunctions

[rebeccahum]

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Describe the solution you'd like

We should add to the $HTMLExecutingFunctions property the following functions:

• insertAdjacentHTML
• outerHTML

What code should be reported as a violation?

(function(){
	divElem.outerHTML = "<div>Hello " + userControlledVal + "</div>"; // Warning.
	divElem.insertAdjacentHTML("","<b>"+ userControlledVal + "</b>"); // Warning.
})();

Additional context

http://blog.blueclosure.com/2017/09/