Wrap section deletion modal in focus trap

[LianaHarris360]

Summary

This pull request includes the addition of FocusTrap to CreateQuizSection in order to maintain focus within the section deletion confirmation modal. Additionally, it addresses the bug where selecting the cancel button failed to exit the modal.

deleteSection.mp4

References

Fixes #12303

Reviewer guidance

1. Create a new quiz.
2. Select options within a section and press delete section.
3. Use the tab key to navigate between CANCEL to DELETE.
4. Confirm that selecting CANCEL closes the modal.

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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

• PR has the correct target branch and milestone
• PR has 'needs review' or 'work-in-progress' label
• If PR is ready for review, a reviewer has been added. (Don't use 'Assignees')
• If this is an important user-facing change, PR or related issue has a 'changelog' label
• If this includes an internal dependency change, a link to the diff is provided

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

[github-actions]

Build Artifacts

Asset type	Download link
PEX file	kolibri-.pex
Windows Installer (EXE)	kolibri-0.17.0a0.dev0+git.149.g0faf7615-windows-setup-unsigned.exe
Debian Package	kolibri_0.17.0a0.dev0+git.149.g0faf7615-0ubuntu1_all.deb
Mac Installer (DMG)	kolibri-0.17.0a0.dev0+git.149.g0faf7615-0.4.2.dmg
Android Package (APK)	kolibri-0.17.0a0.dev0+git.149.g0faf7615-0.1.3-debug.apk
TAR file	kolibri-0.17.0a0.dev0+git.149.g0faf7615.tar.gz
WHL file	kolibri-0.17.0a0.dev0+git.149.g0faf7615-py2.py3-none-any.whl

[rtibbles]

I have not manually tested, but this does seem like the right fix.

Meta-comment, has integrating the FocusTrap component into KModal been mooted previously? If not, should it be?

[rtibbles]

Manual testing of the fix also checks out.