Search: Factor out OldPricingComponent and NewPricingComponent out of UpsellPage component

[oskosk]

Follow-up to #26408

Changes proposed in this Pull Request:

• Moves NewPricingComponent and NewPricingComponent definition outside UpsellPage.
• Moves newPricingArgs out of UpsellPage body

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?

Jetpack product discussion

No

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

No

Testing instructions:

• Go to a connected site with Jetpack Search without a plan.
• Navigate to /wp-admin/admin.php?page=jetpack-search
• Confirm you see the current upsell page with current pricing card
• Navigate to url /wp-admin/admin.php?page=jetpack-search&new_pricing_202208=1
• Confirm there is a brand new upsell page

[github-actions]

Thank you for your PR!

When contributing to Jetpack, we have a few suggestions that can help us test and review your patch:

• ✅ Include a description of your PR changes.
  
• ⚠️ All commits were linted before commit.
  
• ✅ Add a "[Status]" label (In Progress, Needs Team Review, ...).
  
• ✅ Add testing instructions.
  
• ✅ Specify whether this PR includes any changes to data or privacy.
  
• ✅ Add changelog entries to affected projects
  

This comment will be updated as you work on your PR and make changes. If you think that some of those checks are not needed for your PR, please explain why you think so. Thanks for cooperation 🤖

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The e2e test report can be found here. Please note that it can take a few minutes after the e2e tests checks are complete for the report to be available.

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Then, add the "[Status] Needs Team review" label and ask someone from your team review the code.
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Search plugin:

• Next scheduled release: October 4, 2022.
• Scheduled code freeze: September 26, 2022.

[github-actions]

Are you an Automattician? You can now test your Pull Request on WordPress.com. On your sandbox, run bin/jetpack-downloader test jetpack udpate/upsell_page-render-pattern to get started. More details: p9dueE-5Nn-p2