Issue 269, Updated Settings Button to replace tune with settings

[RaviKumarAgurla]

Summary

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References

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Reviewer guidance

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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-0.16.0b13.dev0_git.465.g06aa0051.pex
Windows Installer (EXE)	kolibri-0.16.0b13.dev0+git.465.g06aa0051-unsigned.exe
Debian Package	kolibri_0.16.0b13.dev0+git.465.g06aa0051-0ubuntu1_all.deb
Mac Installer (DMG)	kolibri-0.16.0b13.dev0+git.465.g06aa0051-0.3.0.dmg
Android Package (APK)	kolibri-0.16.0b13.dev0+git.465.g06aa0051-0.1.0-debug.apk
TAR file	kolibri-0.16.0b13.dev0+git.465.g06aa0051.tar.gz
WHL file	kolibri-0.16.0b13.dev0+git.465.g06aa0051-py2.py3-none-any.whl

[MisRob]

Please see learningequality/kolibri-design-system#537 (comment)