Add ProductVariantPrice custom fields ui inputs

[Draykee]

Description

2nd attempt of: #3263

• Added the custom field component to the ProductVariantPrice UI
• Introduced CreateProductVariantPriceInput type as well, for possible future UI updates
  Closes: Expose admin-ui for custom fields on ProductVariantPrice. #3020

Breaking changes

The admin-api schema needs to be updated. The Typescript should not break though, so it should be safe to update.

Screenshots

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Checklist

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• My PR is small and contains a single feature
• I have checked my own PR

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• I have added or updated test cases
• I have updated the README if needed

[vercel]

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Name	Status	Preview	Updated (UTC)
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[github-actions]

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1 out of 2 committers have signed the CLA.
✅ (michaelbromley)[https://github.com/michaelbromley]
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[Draykee]

I have read the CLA Document and I hereby sign the CLA

[Draykee]

No clue where there are changes here.. codegen did it.

[sonarqubecloud]

Quality Gate failed

Failed conditions
7.9% Duplication on New Code (required ≤ 3%)

See analysis details on SonarQube Cloud