curl --request POST \
  --url https://cloud.laravel.com/api/applications/{application}/avatar \
  --header 'Authorization: Bearer <token>' \
  --header 'Content-Type: multipart/form-data' \
  --form avatar='@example-file'

{
  "data": {
    "id": "<string>",
    "type": "applications",
    "relationships": {}
  },
  "included": [
    {
      "id": "<string>",
      "type": "repositories"
    }
  ]
}