#7650317 Limit Global Styles: Update the Privacy settings upgrade notice

Proposed Changes

• Update the copy of the Global Styles gating upgrade nudge in the General -> Privacy settings.
• Also update the “Upgrade” link to automatically suggest the Premium plan when opening the Plans page.

Before	After

Testing Instructions

• Create a new site and apply the wpcom-limit-global-styles sticker.
• Run these changes in a development environment (local, Calypso Live, wpcalypso).
• Open the Site Editor, change some Global Styles and save.
• Open Settings -> General and scroll to the Privacy section.
• ⚠️ Ensure the upgrade notice appears and it uses the updated copy.
• Click on “Upgrade”.
• ⚠️ Ensure it opens the plans comparison page, and the Premium plan is suggested.

Pre-merge Checklist

• Have you written new tests for your changes?
• Have you tested the feature in Simple (P9HQHe-k8-p2), Atomic (P9HQHe-jW-p2), and self-hosted Jetpack sites (PCYsg-g6b-p2)?
• Have you checked for TypeScript, React or other console errors?
• Have you used memoizing on expensive computations? More info in Memoizing with create-selector and Using memoizing selectors and Our Approach to Data
• Have we added the “[Status] String Freeze” label as soon as any new strings were ready for translation (p4TIVU-5Jq-p2)?
• For changes affecting Jetpack: Have we added the “[Status] Needs Privacy Updates” label if this pull request changes what data or activity we track or use (p4TIVU-ajp-p2)?

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