SwitchControl text now toggles checked state

[petemill]

The click event will now fire from the label, whether it is to the left, right, or top of the switch element.

This also converts text from <span /> to <label /> for accessibility and more appropriate renderer defaults (the cursor) to convey that clicking the label will toggle the checked state.

Usages this affects:

• all items in the Brave extension panel (compact and full mode)
• the Clear Browsing Data model
• the MessageBox component
• about:adblock

This is a partial resolution only for #8243 since many usages do not use the built-in switchControl label element but render their own text separately. Changing some of those usages to the switchControl label element causes some minor visual regression which may warrant some discussion. A subsequent PR will address converting these usages, which are not covered by this PR:

• most switches in all sections of about:preferences
• case-sensitivity switch in the findPage dialog

Submitter Checklist:

• Submitted a ticket for my issue if one did not already exist.
• Used Github auto-closing keywords in the commit message.
• Added/updated tests for this change (for new code or code which already has tests).
• Ran git rebase -i to squash commits (if needed).
• Tagged reviewers and labelled the pull request as needed.

Test Plan:

• Open the Clear Browsing Data model or the Brave extension panel
• Verify clicking a switch label causes the checked state to toggle
• Verify no visual regressions

Reviewer Checklist:

Tests

• Adequate test coverage exists to prevent regressions
• Tests should be independent and work correctly when run individually or as a suite ref
• New files have MPL2 license header

[codecov-io]

Codecov Report

Merging #10468 into master will not change coverage.
The diff coverage is 100%.

@@           Coverage Diff           @@
##           master   #10468   +/-   ##
=======================================
  Coverage   54.01%   54.01%           
=======================================
  Files         244      244           
  Lines       21233    21233           
  Branches     3277     3277           
=======================================
  Hits        11470    11470           
  Misses       9763     9763

Flag	Coverage Δ
#unittest	54.01% <100%> (ø)	⬆️

Impacted Files	Coverage Δ
app/renderer/components/common/switchControl.js	96.55% <100%> (ø)	⬆️

[luixxiul]

@petemill thanks for your contribution! Is this PR ready for reviews?

[petemill]

@luixxiul yes indeed. Please also look at #10470 if you can and let me know if you want to merge with this one or not.

[petemill]

Closing in favor of rolling up with #10470