#7568242 Marketplace: Eligibility warning modal add title for non business plans

Proposed Changes

Little upgrade on #68690, we need to add a title for non-business plans on Eligibility warning modal as commented here.

Testing Instructions

1. Go to /plugins with a domain with Business plan and .wordpress.com (not yet migrated)
2. Try to install any plugin (including Free). It should show a modal with the domain change message but with the title Before you continue.

Screenshots

Before	After

Pre-merge Checklist

• 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)?

Fixes #68689