fix(switch): theming issues with focus in dark theme

[Splaktar]

PR Checklist

Please check that your PR fulfills the following requirements:

• The commit message follows our guidelines
• Tests for the changes have been added or this is not a bug fix / enhancement
• Docs have been added, updated, or were not required

PR Type

What kind of change does this PR introduce?

[x] Bugfix
[ ] Enhancement
[ ] Documentation content changes
[ ] Code style update (formatting, local variables)
[ ] Refactoring (no functional changes, no api changes)
[ ] Build related changes
[ ] CI related changes
[ ] Infrastructure changes
[ ] Other... Please describe:

What is the current behavior?

Using the keyboard to focus on a switch in dark mode shows dark ink on a dark background.

Issue Number:
#8518

What is the new behavior?

Using the keyboard to focus on a switch in dark mode shows light ink on a dark background as defined by the spec.

Does this PR introduce a breaking change?

[ ] Yes
[x] No

Other information

This builds upon @rudzikdawid's work in #11417.

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[josephperrott]

Confirmed CLA manually.