**Description**

Don't mark dag as `failed` when `UNSTABLE` status received from Jenkins.
It can be done by adding `allow_unstable: bool` or `success_status_values: list` parameter to `JenkinsJobTriggerOperator.__init__`. For now `SUCCESS` status is hardcoded, any other lead to fail.

**Use case / motivation**

I want to restart a job (`retries` parameter) only if I get `FAILED` status. `UNSTABLE` is okay for me and it's no need to restart.

**Are you willing to submit a PR?**

Yes

**Related Issues**

No

airflow/providers/jenkins/operators/jenkins_job_trigger.py
keep_polling_job = False
                    
                    if build_info['result'] != 'SUCCESS':
                        raise AirflowException(
                            'Jenkins job failed, final state : %s.'
                            'Find more information on job url : %s'
                            % (build_info['result'], build_info['url'])
                        )
                else:
                    self.log.info('Waiting for job to complete : %s , build %s', self.job_name, build_number)
                    time.sleep(self.sleep_time)
            except jenkins.NotFoundException as err:
                
                raise AirflowException(
                    'Jenkins job status check failed. Final error was: ' f'{err.resp.status}'
                )
            except jenkins.JenkinsException as err:
                raise AirflowException(
                    f'Jenkins call failed with error : {err}, if you have parameters '
                    'double check them, jenkins sends back '
                    'this exception for unknown parameters'
                    'You can also check logs for more details on this exception '
                    '(jenkins_url/log/rss)'
                )
        if build_info:
            
            
            return build_info['url']
        return None