WAI-ARIA 1.1 has been superseded by 1.2

## Context

Our documentation references WAI-ARIA 1.1 in various places; for example:

https://vanillaframework.io/accessibility

WAI-ARIA 1.2 was released last summer; we should perform an audit to ensure our components are in compliance with it, and after doing so, should bump up our references from 1.1 to 1.2, much as we did with WCAG 2.2.

Start with the accessibility page linked in the issue and audit the documentation and components for WAI-ARIA 1.1 references and compliance. Compare the findings with WAI-ARIA 1.2 and the earlier WCAG 2.2 update; done means the relevant components are checked and outdated references are updated.

Written by the indexing model from the issue text.