feat: add motion-section components to animate parts of wizards

[thomasguillot]

All Submissions:

• Have you followed the Newspack Contributing guideline?
• Does your code follow the WordPress' coding standards and VIP Go coding standards?
• Have you checked to ensure there aren't other open Pull Requests for the same update/change?

Changes proposed in this Pull Request:

This PR adds a new component: MotionSection.

Wrapping an element/section around such new components allows us to add some subtle animation using the motion.dev library.

This PR also implements this to the dashboard but we might bring something like this to all our screens.

How to test the changes in this Pull Request:

1. Navigation to Newspack > Dashboard
2. Switch to this branch
3. Refresh dashboard

Other information:

• Have you added an explanation of what your changes do and why you'd like us to include them?
• Have you written new tests for your changes, as applicable?
• Have you successfully ran tests with your changes locally?