createTrial method
Adds a user provided Trial to a Study.
Throws a http.ClientException if there were problems communicating with
the API service. Throws a ServiceException if the API method failed for
any reason.
Implementation
Future<Trial> createTrial(CreateTrialRequest request) async {
final url = Uri.https(_host, '/v1beta1/${request.parent}/trials');
final response = await _client.post(url, body: request.trial);
return Trial.fromJson(response);
}