Align NotificationConfigurationService eventTypes descriptions

[compair-steven]

Summary

This updates the eventTypes descriptions in the Notification Configuration API specs so the documented permitted values match the enum values already present in the schema.

Why

While reviewing the OpenAPI definitions, I noticed the TestNotificationConfigurationRequest and TestNotificationConfigurationResponse descriptions list a narrower set of permitted event types than the actual items.enum. The descriptions list 15 values, while the schema enum contains 25 values in both request and response schemas across NotificationConfigurationService v1-v6.

I used the schema enum as the source of truth. The values added to the prose are already present in the current OpenAPI definitions' items.enum; several of them are also represented in neighboring current API surfaces. For example, MarketPayNotificationService-v6 exposes webhook endpoints/examples such as /ACCOUNT_CLOSED, /ACCOUNT_FUNDS_BELOW_THRESHOLD, /DIRECT_DEBIT_INITIATED, and /REFUND_FUNDS_TRANSFER, and FundService-v6 links the direct-debit flow to the DIRECT_DEBIT_INITIATED notification webhook.

The generated Node and Java SDKs also expose the same values on TestNotificationConfigurationRequest and TestNotificationConfigurationResponse, so this change aligns the prose with values that are already visible to SDK users.

This keeps the JSON and YAML definitions consistent for users importing the specs into API tooling.

Testing

• jq empty json/NotificationConfigurationService-v{1,2,3,4,5,6}.json
• ruby -e 'require "yaml"; ARGV.each { |f| YAML.load_file(f) }; puts "YAML parse OK"' yaml/NotificationConfigurationService-v{1,2,3,4,5,6}.yaml
• Verified the request/response eventTypes descriptions now mention every enum value in v1-v6.