AccordionPanel missing aria-level API

[knoobie]

Description

The webcomponent says:

• The WAI ARIA Best Practices also recommend setting aria-level depending
• on what level the headings are. It is hard to determine the level of a heading
• algorithmically, and setting it is not strictly required to have an accessible
• accordion. To keep things easier to use, this element does not set aria-level
• attribute but leaves that to the developer creating an accordion.

Expected outcome

Accordion::setAriaLevel is present and automatically applies the aria-level to all AccordionPanel

AccordionPanel:.setAriaLevel is present and applies aria-label to the corresponding panel

Minimal reproducible example

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Steps to reproduce

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Environment

Vaadin version(s): latest

Browsers

No response

[web-padawan]

Thanks for the issue. This is a duplicate of vaadin/web-components#6900.