Improve documentation for <select> controlled component

[nupurgrover]

In the React documentation for forms, there is only a footnote on using the controlled component with the multiple attribute. I recently spent some time getting it to work for my use case and I feel having better documentation would have sped things up. My use case involved populating the <option> elements from JSON data being returned from the server, for a select component with the multiple attribute. I am happy to contribute the documentation and raise a PR :)

[alexkrolick]

A PR would be very welcome!

[nupurgrover]

Okay, I will submit one in the next couple of days!

[rickhanlonii]

The new place this exists in the docs is here: https://react.dev/reference/react-dom/components/select#enabling-multiple-selection

I think we could add a new Usage example for "Controlling a select box with multiple options"