fix: Use text color for Checkbox.Item label

[kamui545]

I noticed there is an inconsistency between the RadioButton.Item and Checkbox.Item components.
Radio is using colors.text for its label, however, checkbox is using colors.primary.

This PR attempts to fix that by also using colors.text for the Checkbox.Item component.

Snacks from the doc for quick preview of the issue:

• Radio
• Checkbox

[callstack-bot]

Hey @kamui545, thank you for your pull request 🤗. The documentation from this branch can be viewed here.

[Trancever]

Thanks for the PR! Please make sure tests and lint are passing if possible 🙏 Once it's done we will merge the PR.

[kamui545]

@Trancever Done : )

[Trancever]

Thanks!