Jetpack Overlay - Add dismiss button

[Gio2018]

Fixes #19177

This PR adds an "x" dismiss button to the top-trailing corner of the Jetpack overlay.
It also contains some layout and fonts adjustments, as well as an updated logo animation.

dark mode	light mode

Known issues: the landscape layout will be addressed in a separate PR

To test:

• Checkout this branch and enable the jetpackBottomSheet feature flag
• Build/run
• Go to My Site/Home
• Tap the "Jetpack powered" badge
• Make sure the overlay appears, and contains a dismiss button on the top-trailing corner
• Tap that button, and make sure the overlay dismisses itself

Regression Notes

1. Potential unintended areas of impact
   None

2. What I did to test those areas of impact (or what existing automated tests I relied on)

3. What automated tests I added (or what prevented me from doing so)

PR submission checklist:

• I have completed the Regression Notes.
• I have considered adding unit tests for my changes.
• I have considered adding accessibility improvements for my changes.
• I have considered if this change warrants user-facing release notes and have added them to RELEASE-NOTES.txt if necessary. Not released

[wpmobilebot]

You can test the changes in Jetpack from this Pull Request by:

• Clicking here or scanning the QR code below to access App Center
• Then installing the build number pr19182-61df373 on your iPhone

If you need access to App Center, please ask a maintainer to add you.

[wpmobilebot]

You can test the changes in WordPress from this Pull Request by:

• Clicking here or scanning the QR code below to access App Center
• Then installing the build number pr19182-61df373 on your iPhone

If you need access to App Center, please ask a maintainer to add you.

[twstokes]

👋 This is looking good! I left a comment on the PR.

I tested:

• Light / Dark mode
• iPhone / iPad
• VoiceOver

[twstokes]

LGTM @Gio2018! 🚀