A11Y: various issues

[andrejkaPry]

Hi there, we stumbled upon various issues regarding a11y. Could you please navigate these?

1. Category tabs:

• currently possible to navigate only via Tab key, not arrows.
• not properly announced for screen readers, e.g.: 'Smileys and People, selected, tab, 1 of 8' -> incorrect label name

2. Skin Tone selection:

• not announcing skin tone selected, only role are announced as 'Choose skin tone, button'
• after choosing the skin tone, focus disappears

3. Emoji navigation:

• from Search input is possible to navigate only via arrows not Tab key

4. Emoji picker cannot be dismissed by Esc key - need to press few times.

[andrejkaPry]

First two already carry this fix, if you'd approve we could merge.

[PatrickJoannisse]

We had a WCAG audit recently and found those issues are also impacting us.

[andrejkaPry]

Hey @PatrickJoannisse, we already forked and fixed the issues as we had to move forward with this. https://github.com/slidoapp/emoji-mart
It also is already published on https://www.npmjs.com/package/@slidoapp/emoji-mart, https://www.npmjs.com/package/@slidoapp/emoji-mart-react, https://www.npmjs.com/package/@slidoapp/emoji-mart-data. Feel free to use it :)