fix(): use is-dark for highligh dark theme (#2053)

[JulieMarie]

Description

Missed a commit that needed to be on 4.x.x

What's included?

Test Steps

• [ ] npm run start
• [ ] then this
• [ ] finally this

General Tests for Every PR

• [ ] npm run start still works.
• [ ] npm run lint passes.
• [ ] npm run stylelint passes.
• [ ] npm test passes and code coverage is not lower.
• [ ] npm run build still works.

Screenshots or link to StackBlitz/Plunker

[owilliams320]

:tada: This PR is included in version 4.17.4 :tada:

The release is available on:

• v4.17.4
• GitHub release

Your semantic-release bot :package::rocket: