[core] fix(Menu): add a11y roles and aria attributes

[bvandercar-vt]

Fixes #5320

Checklist

• [N/A ] Includes tests
• [N/A] Update documentation

Changes proposed in this pull request:

Fix Menu and MenuItem a11y roles for a menu per this example: https://w3c.github.io/aria-practices/examples/menubar/menubar-navigation.html

Reviewers should focus on:

the above example aria menu

[bvandercar-vt]

I am on Windows 10 and am getting errors when running yarn verify/yarn compile, and cannot run yarn test either-- can one of the Devs please check out this branch and run the test I've written plus whatever else needs to be done?

[adidahiya]

Thanks for your contributions, and sorry about the trouble building the project on Windows. Could you share some of your build errors in this issue? Other contributors have had similar problems: #4221

[adidahiya]

mostly looks good, just one small comment