fix: apply active class to submenu items

[guidemetothemoon]

Description

Describe the issue fixed here
Recently support for dropdown has been implemented in navigation menu, ref. #344 . There's a small issue there that the menu section will not be underlined as active if any menu options other than the first one will be chosen from the dropdown. So in exampleSite if you had a structure like this:

Accomplishments:
    Awards
    Certifications

Then Accomplishments section will be marked as active only if Awards is an active page but not when Certifications is an active page.
This has now been fixed and parent section will be marked as active as long as any of the child sections are currently active.

Issue Number:

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Checklist

Yes, I included all necessary artefacts, including:

• Tests
• Documentation
• Implementation (Code and Ressources)
• Example

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Testing Checklist

Yes, I ensured that all of the following scenarios were tested:

• Desktop Light Mode (Default)
• Desktop Dark Mode
• Desktop Light RTL Mode
• Desktop Dark RTL Mode
• Mobile Light Mode
• Mobile Dark Mode
• Mobile Light RTL Mode
• Mobile Dark RTL Mode

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[sonarcloud]

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