Docs: Async behavior

[lmiller1990]

I decided not to write about <Suspense> yet, because it's experimental and it doesn't appear to officially be documented anywhere (can you even use it without setup? I have no idea - and we are sticking to the options API in the docs).

[afontcu]

Looks great!! 🎉 Left some comments here and there – some are small typos, other suggest alternative ways of exposing things, and a few add additional information which might come in handy.

[afontcu]

Suggested change

Surprisingly, this fails! The reason is although `count` is increased, Vue will not update the DOM until the next "tick" or "render cycle". For this reason, the assertion will be called before Vue updates the DOM. This has to do with the concept of "marcotasks", "microtasks" and the JavaScript Event Loop. You can read more details and see a simple example [here](https://javascript.info/event-loop#macrotasks-and-microtasks).

Surprisingly, this fails! The reason is although `count` is increased, Vue will not update the DOM until the next "tick" or "render cycle". For this reason, the assertion will be called before Vue updates the DOM. This has to do with the advanced concepts of "macrotasks", "microtasks" and the JavaScript Event Loop. You can read more details and see a simple example [here](https://javascript.info/event-loop#macrotasks-and-microtasks).

[afontcu]

Actually… should these advanced concepts be mentioned before the "simple" solution of using await? It might be good to flip them: first the simple solution, and then, if anyone's interested, we can mention micro/macro tasks and add some interesting links.

[lmiller1990]

Sure.

I dropped a link to an article by you about nextTick in there as well :)

[afontcu]

to highlight the appropriate line:

Suggested change

	```js
	```js {7}