fix(5018): compare wholeText instead of data

[skippednote]

This PR addresses #5018.
Instead of comparing the input with data property on the Text Node, I've changed it to wholeText.

[Conduitry]

Is this something that it's possible to write a test for? I note that the original bug wasn't something I could reproduce on Firefox - I was only seeing it on Chrome - so there's something peculiar going on here, and I don't know what behavior JSDOM has - and I also don't know whether the behavior of one browser or the other could be considered a bug.

Also, do you know what the support of wholeText is? We'd like to try not to use things that aren't easily transpilable or polyfillable on the last couple versions of IE. I see on https://caniuse.com/#feat=mdn-api_text_wholetext that it's supported on IE11, but I don't see any information about earlier than that.

[skippednote]

@Conduitry I've been trying to figure out how to test this, but haven't had any luck so far.
The following doesn't help replicate the behaviour we see in the repl. Any pointers on how to proceed?

div.textContent = 'something';
div.dispatchEvent(new InputEvent('input'));

I'll be check support for wholeText in previous versions on IE using BrowserStack and report back here.

@Conduitry I just checked, wholeText is supported in IE9 and above.

[skippednote]

@Conduitry I've figured out a way to test it by replicating the current behaviour. Here is a vanilla JS emulation https://jsbin.com/ziperitova/edit?html,js,output