curl --request GET \
  --url https://api.example.com/api/Messages/Emails/{messageId}

{
  "id": 123,
  "cc": "<string>",
  "subject": "<string>",
  "body": "<string>",
  "createdByID": 123,
  "fromCustomerID": 123,
  "fromName": "<string>",
  "fromEmail": "<string>",
  "jobID": 123,
  "createdDate": "2023-11-07T05:31:56Z",
  "sendAfter": "2023-11-07T05:31:56Z",
  "placementID": 123,
  "changeRequestID": 123,
  "placeholdersEntityID": 123,
  "placeholdersPlayerID": 123
}