Add new inline banner in key metrics settings for existing users who saved "Sell products or services" legacy site purpose answer

[zutigrm]

Feature Description

As part of the work carried on in #9489 the now legacy site purpose answer "Sell products or services" was split into "Sell products" and "Provide services" answers. This issue should implement the new inline banner that will be surfaced in the key metrics admin settings section for existing users who previously saved legacy "" answer.

Figma design can be found here

Check Splitting “Sell products or services” site purpose answer section of the design doc

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Do not alter or remove anything below. The following sections will be managed by moderators only.

Acceptance criteria

• Existing users that have previously saved "Sell products or services" answer for site purpose are shown the new inline banner in the Key metrics section of the admin settings
• Banner should match the content and design from Figma
• It should stay visible in both Preview and Edit mode, above the selected answer/answers list
• Clicking the Got it CTA dismisses the banner
• Check Splitting “Sell products or services” site purpose answer section of the design doc

Implementation Brief

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Test Coverage

QA Brief

Changelog entry

[eugene-manuilov]

AC ✔