Fixes to Automattic/martech#1718

Proposed Changes

This PR implements the requested changes in the linked issue above regarding the banner carousell in /stats:

1. Show the GA promo banner for sites on the Free plan and the Personal plan.
2. Automatically rotate the banner by the given period. Currently I’ve anecdotally set it as 5 secs.

The automatical rotation mechanism is lifted into the underlying <DotPager> component, since it’s a general functionality that the rest of the codebase can be benefited from as well.

Screencast:

Testing Instructions

1. Logging into a Free site, visit /stats and confirm that the GA promo banner exists.
2. Logging into a Personal site, visit /stats and confirm that the GA promo banner exists.
3. Dismissing the GA promo banner by clickgin “hide this” should make the banner disappear even after refreshing.
4. Confirm that the carousell rotates automatically. After manually navigating back-and-forth the banners, it should still advance automatically.

Pre-merge Checklist

• Has the general commit checklist been followed? (PCYsg-hS-p2)
• 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)?