Fix incorrect left padding of checkout address form messages

[wojtekn]

Related to #95816

Proposed Changes

I propose to fix the incorrect space that appears on the left side of checkout billing address form validation messages.

Why are these changes being made?

To provide consistent UI.

Testing Instructions

1. Open Calypso locally or use a Calypso Live link
2. Navigate to https://wordpress.com/domains/
3. Choose a domain and proceed through the following steps to add it to the cart
4. Edit contact information fields and ensure they are empty
5. Click 'Continue to payment'
6. Confirm that validation messages under fields are aligned correctly

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-126466

Jetpack Cloud live (direct link)

https://calypso.live?image=registry.a8c.com/calypso/app:build-126466&env=jetpack

Automattic for Agencies live (direct link)

https://calypso.live?image=registry.a8c.com/calypso/app:build-126466&env=a8c-for-agencies

[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.

[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/field-validation-message-spacing on your sandbox.

[sirbrillig]

Thanks for spotting this. I wonder when that regression happened. 🤔

[wojtekn]

@sirbrillig thanks for reviewing it.

I think it might have popped out after adding left padding in 1954928. In wp-contact-form.tsx we have not been setting the the left padding, so the other one was used.