Add GraphQL mutation to approve or reject deployment

What does this MR do and why?

This merge request adds a new GraphQL mutation to approve or reject a deployment.

Please note: I followed the naming conventions section of the GraphQL API style guide when choosing the name of this mutation.

Resolves #388527 (closed).

How to set up and validate locally

To validate locally, please follow the steps below.

• In your local GDK setup, create a new project if you don't have one already.
• Inside that project, create an environment in Deployments > Environments.
• Protect the environment you had just created in Settings > CI/CD > Protected Environments.
• Add the following .gitlab-ci.yml file to the project:

image: alpine:latest

say_test:
  stage: test
  script: echo 'testing..'

deploy_production:
  stage: deploy
  script:
    - echo 'deploying..'
    - echo 'deployed!'
  environment: production

• Run a pipeline inside the project from CI/CD > Pipelines.
• Ensure a deployment is created in Deployments > Environments. The deployment should be blocked waiting for approval.
• Log out of your account, and then login using a different user.
• Visit GraphiQL Explorer on your local GitLab instance.
• Paste the GraphQL query from the section below. Make sure to replace DEPLOYMENT_ID with the actual deployment id.
• Verify the deployment is approved and the deploy_job is green.

Note: You can do the same steps above to also reject the deployment.

Query Example

mutation {
  approveDeployment(
    input: {id: "gid://gitlab/Deployment/DEPLOYMENT_ID", status: APPROVED, comment: "Nice one!"}
  ) {
    deploymentApproval {
      comment
      createdAt
      status
      updatedAt
    }
    errors
  }
}

Response

{
  "data": {
    "approveDeployment": {
      "deploymentApproval": {
        "comment": "Nice one!",
        "createdAt": "2023-02-15T10:15:51Z",
        "status": "APPROVED",
        "updatedAt": "2023-02-15T10:15:51Z"
      },
      "errors": []
    }
  }
}

MR acceptance checklist

This checklist encourages us to confirm any changes have been analyzed to reduce risks in quality, performance, reliability, security, and maintainability.

• I have evaluated the MR acceptance checklist for this MR.