fix: unit button active state (backport)

[Anas12091101]

Description

This is a backport of #2617

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  Before

Screen.Recording.2025-11-12.at.5.45.01.PM.mov

After

Screen.Recording.2025-11-12.at.1.20.36.PM.mov

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[openedx-webhooks]

Thanks for the pull request, @Anas12091101!

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[bradenmacdonald]

Looks good. Thanks so much!