Promote a deployment to the next environment

curl --request POST \
  --url https://api.us.poly.ai/v1/agents/{agentId}/deployments/{deploymentId}/promote \
  --header 'Content-Type: application/json' \
  --header 'X-API-KEY: <api-key>' \
  --data '
{
  "deploymentMessage": ""
}
'

{
  "deployment": {
    "id": "<string>",
    "accountId": "<string>",
    "agentId": "<string>",
    "environment": "<string>",
    "artifactVersion": "<string>",
    "version": "<string>",
    "createdBy": "<string>",
    "createdAt": "<string>",
    "metadata": {}
  },
  "testRunIds": [
    "<string>"
  ]
}