Description

This PR makes the heading level for the dashboard sections and widgets customizable by adding a property rootHeadingLevel to Dashboard.

• The defaults are unchanged.
• The titles are now rendered as divs instead of h2 and h3. Instead, the level is applied using the aria-level attribute on the title element.

Part of #8779

Type of change

• Bugfix
• Feature

Checklist

• I have read the contribution guide: https://vaadin.com/docs/latest/contributing/pr
• I have added a description following the guideline.
• The issue is created in the corresponding repository and I have referenced it.
• I have added tests to ensure my change is effective and works as intended.
• New and existing tests are passing locally with my change.
• I have performed self-review and corrected misspellings.
• Enhancement / new feature was discussed in a corresponding GitHub issue and Acceptance Criteria were created.