PFE-Dropdown has incorrect aria and a11y setup

[wesruv]

Description of the issue

This was noticed on PFE 1.x, but I suspect it might also be in 2.x, full discussion is here: https://chat.google.com/room/AAAA0siaVdA/V0r-JRHGmOY

It should follow the aria/accessibility setup from: https://pattern-library.dequelabs.com/components/selects

Basically it should be following the listbox pattern, instead of a menu, menu has very specific expectations similar to the "File" menu in applications:

While the term "menu" is generically used a term used to describe site navigation, the menu role is for a list of action or functions that require complex functionality, such as composite widget focus management and first-character navigation
From: https://developer.mozilla.org/en-US/docs/Web/Accessibility/ARIA/Roles/menu_role

Impacted component(s)

• pfe-dropdown

[wesruv]

I don't see this component in RHDS yet, adding the tag because I'm guessing it might be headed there?

[bennypowers]

The next step for pfe-dropdown will be to align it with PFv4. We could address this during that process. Is it the case that you will want dropdown in RHDS, being the successor to pfe 1.x dropdown? in that case please fill out a request for new component there.

[wesruv]

Cool, I think it'd be great to have this in RHDS, I'd guess @kylebuch8 && @TylerMartin5 would also be interested. Made a ticket: RedHat-UX/red-hat-design-system#425

[bennypowers]

See also #2049