Fix keyboard functionality for rux-tabs

[kiley-mitti]

Brief Description

Borrowed some code from Mark for the keyboard functionality of tabs, and then inserted my own roving tab index logic. Now tabs work as they should. They currently do not automatically activate on focus but a keyboard user can use the arrow keys to select the appropriate tab and hit enter to activate it.

JIRA Link

ASTRO-4952

Related Issue

Part of focus state work.

General Notes

Motivation and Context

tab keyboard control didn't work as one would expect. now it does.

Issues and Limitations

I am sick. please look at code and critique my potato brain.

Types of changes

• [x] Bug fix
• [ ] New feature
• [ ] Breaking change

Checklist

• [ ] This PR adds or removes a Storybook story.
• [x] I have added tests to cover my changes.
• [x] Regressions are passing and/or failures are documented
• [x] Changes have been checked in evergreen browsers

[changeset-bot[bot]]

⚠️ No Changeset found

Latest commit: 16eb447972538c88005814da4ef55bcc85a7d37c

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[kiley-mitti]

Added some tests to cover the keyboard functionality changes! @markacianfrani do these look ok? They're all passing. :)

[kiley-mitti]

I also made a change to where role="tab" lives. We can't put it directly on because it is tied to focus so needs to be where tabindex lives.

[kiley-mitti]

Added a new test for disabled tabs! One more look? :)