Prevent infinite redirect after processing site on onboarding flow

[paulopmt1]

Related to #97938

Proposed Changes

• We're deferring the submit to give React time to update hasActionSuccessfullyRun and avoid infinite redirects.

Why are these changes being made?

• To prevent infinite loops and console errors

Testing Instructions

• Open the http://calypso.localhost:3000/setup/onboarding flow
• Finish the flow and note that after the /setup/site-setup/processing step we don't get the Maximum update depth exceeded error anymore
• Make sure the redirect works as expected

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 UI changes, have we tested the change in various languages (for example, ES, PT, FR, or DE)? The length of text and words vary significantly between languages.
• 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-aUh-p2)?

[github-actions]

Calypso Live (direct link)

https://calypso.live?image=registry.a8c.com/calypso/app:build-129269

Jetpack Cloud live (direct link)

https://calypso.live?image=registry.a8c.com/calypso/app:build-129269&env=jetpack

Automattic for Agencies live (direct link)

https://calypso.live?image=registry.a8c.com/calypso/app:build-129269&env=a8c-for-agencies

[matticbot]

This PR modifies the release build for the following Calypso Apps:

For info about this notification, see here: PCYsg-OT6-p2

• notifications
• wpcom-block-editor

To test WordPress.com changes, run install-plugin.sh $pluginSlug fix/error-while-processing-site on your sandbox.

[matticbot]

This PR does not affect the size of JS and CSS bundles shipped to the user's browser.

Generated by performance advisor bot at iscalypsofastyet.com.

[zaguiini]

Confirmed I'm not getting the error on the console anymore.