Blocks: use new useResizeObserver hook

[coder-karen]

Fixes #39922
Fixes VULCAN-92

Proposed changes:

• This PR updates the useResizeObserver usage (from @wordpress/compose) in two instances: in the Story block, and the Image Compare block.
• The new API and behaviour of this hook was introduced in WordPress 6.7, which is now our minimum supported version of WordPress.
• I've included border-box as the box model, though for the blocks I notice no difference in testing. This appears to be more beneficial for responsive designs as it includes padding and borders, so chose to keep it.
• This does not include changes to the instance in the forms package (being dealt with here), nor the Tiled Gallery block instance as this is in the edit.native.js file, which is used on mobile (checked in with mobile here: p1746182839589319-slack-C0180B5PRJ4 )

Other information:

• Have you written new tests for your changes, if applicable?
• Have you checked the E2E test CI results, and verified that your changes do not break them?
• Have you tested your changes on WordPress.com, if applicable (if so, you'll see a generated comment below with a script to run)?

Jetpack product discussion

n/a

Does this pull request change what data or activity we track or use?

No.

Testing instructions:

On a local development site or Jurassic Ninja or WoA site with this PR applied using the beta tester plugin, or on a sandboxed Simple site with this PR applied by using the commands in the generated comment below:

• Add a Story block to a post. Ensure it works as expected in the editor and front-end
• Add an Image Compare block to a post. Ensure it works as expected in the editor and front-end

[github-actions]

Are you an Automattician? Please test your changes on all WordPress.com environments to help mitigate accidental explosions.

• To test on WoA, go to the Plugins menu on a WoA dev site. Click on the "Upload" button and follow the upgrade flow to be able to upload, install, and activate the Jetpack Beta plugin. Once the plugin is active, go to Jetpack > Jetpack Beta, select your plugin (Jetpack), and enable the update/useResizeObserver-hook-usage branch.
• To test on Simple, run the following command on your sandbox:

bin/jetpack-downloader test jetpack update/useResizeObserver-hook-usage

Interested in more tips and information?

• In your local development environment, use the jetpack rsync command to sync your changes to a WoA dev blog.
• Read more about our development workflow here: PCYsg-eg0-p2
• Figure out when your changes will be shipped to customers here: PCYsg-eg5-p2

[github-actions]

Thank you for your PR!

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[jp-launch-control]

Code Coverage Summary

Coverage changed in 2 files.

File	Coverage	Δ%	Δ Uncovered
projects/plugins/jetpack/extensions/blocks/story/player/player-ui.js	1/63 (1.59%)	-0.11%	4 💔
projects/plugins/jetpack/extensions/blocks/image-compare/edit.js	15/37 (40.54%)	1.83%	3 ❤️‍🩹

Full summary · PHP report · JS report

_{Coverage check overridden by I don't care about code coverage for this PR Use this label to ignore the check for insufficient code coveage. .}

[darssen]

Not very familiar with the code, but was able to test in all 3 environments (self-hosted, woA and simple) and blocks were working fine without errors.

Thanks for taking care of this @coder-karen