Steps to reproduce (assumes ChromeVox or similar))

1. Open https://elastic.github.io/eui/#/navigation/context-menu in a new tab.
2. Tab to the "Click me to load a context menu" button
3. Press enter and listen to the screen reader

Actual Result

"View Options Show Fullscreen Share this Dashboard Edit / add Panels Display Options"

Expected Result

"View Options, Show Fullscreen, Button Selected 1 of 4"

Category: #730: Elastic UI Context Menu Accessibility
Relevant WCAG Criteria: 3.2.3 Consistent Navigation