fix(component-header):highlight nav parent if subitem active

[scott-williams-az]

Description

Has anyone noticed on their site that if they have multiple columns in their menu items that anything not in the first column will not highlight the menu navigation when they are on that page?

Links

• Unity reference site
• JIRA ticket
• Unity Design Kit

Checklist

• [ ] Unity project successfully builds from root yarn install & yarn build
• [ ] Commits do not contain multiple scopes
• [ ] Add/updated examples
• [ ] Add/updated READMEs/docs
• [ ] No new console errors
• [ ] Accessibility checks

Browsers

• [ ] Chrome
• [ ] Safari
• [ ] Firefox
• [ ] Edge

Images

[scott-williams-az]

This could use some discussion, as I don't necessarily think the additional prop for currentPage is needed

and the change in the first commit actually doesn't do anything (at least for WS2) since we are never setting a sub menu item with selected=true