[docs] Fix statement about the order of bind: and on:

[gtm-nayan]

Turns out I kinda lied in #6887 (oops). The order of definition only affects things when the binding is based on the same event (see #7212). Hopefully it should be clear enough now.

Caveat: according to this SO thread, it'll not hold true in old (pre IE8) browsers, but we don't really have to care about that do we?

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[dummdidumm]

While this is correct, I'm a little hesitant to add it like this to the docs, simply because it might be a little bloated. While not 100% correct, the previous statement was easier to read and therefore understand. The new way requires elaboration on event timings etc.
A good middle ground might be to just clarify the wording a little - noting that the bound value and the event that is used for that binding under the hood are order-aware.

[Conduitry]

I don't really see what was wrong with the old one, but I wouldn't be against adjusting it to mention something about how each bind: represents (in part) an implicit on:, and all of these are attached in order.

I do agree that what's in this PR is too wordy for the type of documentation it's being proposed for.

[gtm-nayan]

@Conduitry how about now?