Tweak navbar overflow logic to catch selected items

[rtibbles]

Summary

• Updates nav link in navbar check to ensure the link is completely bounded by the navbar
• If not, it is included in the dropdown menu
• Also skips attempting to navigate if we are already on the selected page from the dropdown menu

References

Fixes #11776

Reviewer guidance

Test on a 375 pixel wide screen, click into the info page on the device tab.
Ensure that the navigation overflow is still visible.

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Testing checklist

• Contributor has fully tested the PR manually
• If there are any front-end changes, before/after screenshots are included
• Critical user journeys are covered by Gherkin stories
• Critical and brittle code paths are covered by unit tests

PR process

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• If this is an important user-facing change, PR or related issue has a 'changelog' label
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Reviewer checklist

• Automated test coverage is satisfactory
• PR is fully functional
• PR has been tested for accessibility regressions
• External dependency files were updated if necessary (yarn and pip)
• Documentation is updated
• Contributor is in AUTHORS.md

[marcellamaki]

Thanks @rtibbles - manual QA checks out on the additional improvements and the redundant nav logic. There might be some additional funky edge cases when resizing small browser screens and doing lots of navigation in between resizing, but as we discussed separately on slack, I think for now, it's okay to wait on that. We can consider all of the complex edge cases as we start thinking about moving some of the responsibility of this into a KComponent.

[github-actions]

Build Artifacts

Asset type	Download link
PEX file	kolibri-0.16.0b11.dev0_git.23.g3d3406ce.pex
Windows Installer (EXE)	kolibri-0.16.0b11.dev0+git.23.g3d3406ce-unsigned.exe
Debian Package	kolibri_0.16.0b11.dev0+git.23.g3d3406ce-0ubuntu1_all.deb
Mac Installer (DMG)	kolibri-0.16.0b11.dev0+git.23.g3d3406ce-0.3.0.dmg
Android Package (APK)	kolibri-0.16.0b11.dev0+git.23.g3d3406ce-0.1.0-debug.apk
TAR file	kolibri-0.16.0b11.dev0+git.23.g3d3406ce.tar.gz
WHL file	kolibri-0.16.0b11.dev0+git.23.g3d3406ce-py2.py3-none-any.whl