[A11Y] Registration form captcha accessibility

[foxbunny]

Describe the bug

The captcha playback and refresh buttons are not screen-reader friendly.

To Reproduce
Steps to reproduce the behavior:

1. Go to a registration form using a screen reader
2. Let the screen reader read the form
3. Observe that both buttons on the captcha control are announced as just "button"

Expected behavior

The buttons are announced as "play" and "refresh CAPTCHA"

Additional context
https://www.w3.org/WAI/WCAG21/Understanding/labels-or-instructions.html