feat(accordion): accordion item header

[Powerplex]

TASK: #2058

Description, Motivation and Context

Managing heading levels for Accordion items triggers. As per ARIA accordion pattern guidelines:

Each accordion header button is wrapped in an element with role [heading](https://w3c.github.io/aria/#heading) that has a value set for [aria-level](https://w3c.github.io/aria/#aria-level) that is appropriate for the information architecture of the page.

https://www.w3.org/WAI/ARIA/apg/patterns/accordion/

Types of changes

• [x] ✨ New feature (non-breaking change which adds functionality)

[codecov[bot]]

Codecov Report

Attention: Patch coverage is 50.00000% with 3 lines in your changes missing coverage. Please review.

Project coverage is 97.56%. Comparing base (309ec9b) to head (bef11fc). Report is 2 commits behind head on main.

Files	Patch %	Lines
...s/components/accordion/src/AccordionItemHeader.tsx	40.00%	3 Missing :warning:

Additional details and impacted files

```diff @@ Coverage Diff @@ ## main #2245 +/- ## ========================================== - Coverage 97.61% 97.56% -0.05% ========================================== Files 759 760 +1 Lines 6000 6006 +6 Branches 2098 2136 +38 ========================================== + Hits 5857 5860 +3 - Misses 141 144 +3 Partials 2 2 ```

:umbrella: View full report in Codecov by Sentry.
:loudspeaker: Have feedback on the report? Share it here.