[v4] Tailwind config: `platformSelect` on color with alpha value breaks css variables on 2nd platform

[mrzachnugent]

Describe the bug Given a tailwind config that uses platformSelect for a color with an alpha value,

 background: platformSelect({
          android: 'rgb(var(--android-background) / <alpha-value>)',
          ios: 'rgb(var(--background) / <alpha-value>)',
        })

When you start the app on the second platform (iOS in the example above) Then the css variables no longer work on iOS.

To Reproduce Steps to reproduce the behavior:

1. Clone the following minimal reproduction repo: https://github.com/mrzachnugent/nw-platform-select-alpha-value
2. Install the dependencies and start the iOS app: npm i && npm run ios
3. The screen should be a red color with an opacity of 30%, instead it is the default screen color.

Expected behavior The css variables work for the second platform as it does for the first platform. In the minimal repo, the iOS screen should be a red color with an opacity of 30%.

To Reproduce working version for first platform (2 options) With Android

1. Run the android app: npm run android
2. When the app loads, you will see the screen will be a red color with an opacity of 30%

With iOS

1. Checkout the branch with iOS as first platform in platform select: git checkout @zach/working-first-platform
2. Run the android app: npm run ios
3. When the app loads, you will see the screen will be a red color with an opacity of 30%

Screenshots Current behavior:

Expected behavior:

Additional context Add any other context about the problem here.