NPA-5375: OAS version bump 1.8.0 -> 1.9.0

[lelliott-hippo]

Pull Request

🧾 Ticket Link

https://nhsd-jira.digital.nhs.uk/browse/NPA-5373

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📄 Description/Summary of Changes

OAS version: 1.8.0 -> 1.9.0

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🧪 Developer Testing Carried Out

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🧪 Reviewer Testing Required

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✅ Developer Checklist

• PR title follows the format: NPA-XXXX: <short-description>
• Branch name follows the convention: <type>/NPA-XXXX-<short-description>
• Commit messages follow the template: NPA-XXXX: <short-description>
• All acceptance criteria from the Jira ticket are addressed
• Automated tests (unit/integration/API/infrastructure etc. tests) are added or updated
• The traceability matrix is updated
  with
  new tests or requirements
• Assignees and appropriate labels (e.g. terraform, documentation) are added

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👀 Reviewer Checklist

• Changes meet the acceptance criteria of the Jira ticket
• Code is able to be merged (no conflicts and adheres to coding standards)
• Sufficient test evidence is provided (manual and/or automated)
• Infrastructure/operational/build changes are validated (if applicable)

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🚀 Post-merge

After merging and deploying changes to the sandbox, Postman collection or spec examples please run the Run Postman
collection workflow.

This will run the tests within the collection to check that the sandbox is working as expected once deployed.

[github-actions]

This branch is work on a ticket in the NHS Digital NPA JIRA Project. Here's a handy link to the ticket:

NPA-5373