ESLint: update error message for @emotion/css with info about the useCx hook

[ciampo]

Description

Update ESLint error message when importing from the @emotion/css package.

The updated message reflects how the useCx hook should be used instead of importing the cx function directly.

How has this been tested?

Install locally, and remove this comment from packages/components/src/utils/hooks/use-cx.ts — the updated error message should be shown.

Screenshots

N/A

Types of changes

New feature (updated ESLint error message)

Checklist:

• My code is tested.
• My code follows the WordPress code style.
• My code follows the accessibility standards.
• I've tested my changes with keyboard and screen readers.
• My code has proper inline documentation.
• I've included developer documentation if appropriate.
• N/A I've updated all React Native files affected by any refactorings/renamings in this PR (please manually search all *.native.js files for terms that need renaming or removal).

[gziolo]

Nice, thank you for clarification 👍

[sarayourfriend]

LGTM!