Elevate fire event page in prep for merge

[jacobparis]

As per conversation on #490 (and #485), the event firing utilities are largely universal and independent of the testing library family products they're imported into

This PR moves the existing Fire Event page from its nested folder in DOM Testing Library to the top level in preparation for it to be merged with the docs from User Event

@MatanBobi had begun working on #485 so I followed his model for the page structure to keep things consistent

This PR includes a 301 Redirect which, assuming I implemented it correctly, will cover all traffic going to the original Fire Event page and make this a non-breaking change

I'm interested in any feedback or pushback with the goal of being able to migrate the docs from User Event to this repository in short order

[MatanBobi]

Hi @jacobparis !
The work I did in this issue is still a WIP, I will issue a PR once done, but as you can see in the comments there, the structure will probably change and the Queries page won't be under "Getting Started"..

[jacobparis]

Closing since the merge isn't happening now and when it does this will be horribly out of date

[nickmccurdy]

This still seems like a useful change to me, even without merging user-event. Perhaps we could reopen it and use similar formatting for user-event's page in #519.

[nickmccurdy]

Seems like this was completed elsewhere.