fix(connector): [adyen] dynamic fields

[AkshayaFoiger]

Type of Change

• Bugfix
• New feature
• Enhancement
• Refactoring
• Dependency updates
• Documentation
• CI/CD

Description

This PR resolves the following issues

1. Change Klarna required field path for country from required_fields.payment_method_data.pay_later.klarna.billing_country to payment_method_data.billing.address.country

Additional Changes

• This PR modifies the API contract
• This PR modifies the database schema
• This PR modifies application configuration/environment variables

Motivation and Context

How did you test it?

Test case
Create a payment with payment body limited by required fields.

1. Klarna

Checklist

• I formatted the code cargo +nightly fmt --all
• I addressed lints thrown by cargo clippy
• I reviewed the submitted code
• I added unit tests for my changes where possible

[semanticdiff-com]

Review changes with  

Changed Files

File	Status
crates/router/src/core/payments.rs	80% smaller
api-reference-v2/openapi_spec.json	0% smaller
api-reference/openapi_spec.json	0% smaller
crates/api_models/src/enums.rs	0% smaller
crates/router/src/configs/defaults/payment_connector_required_fields.rs	0% smaller