title: How to trigger a specific job in gitlab
body: <p>I want to run a specific job in a pipeline , I thought assigning a tag for the job and then specifying this tag again in the post method will fulfill my needs .The problem is when I trigger using the api(post) , all the jobs in the pipeline are triggered event though only one of this tagged .  </p>
  
  <p>gitlab-ci.yml :</p>
  
  <p>job1:
    script:
      - echo "helloworld!"
    tags : [myTag]</p>
  
  <p>job2:
    script:
      - echo "hello gitlab!"</p>
  
  <hr>
  
  <p>the api call :
  curl -X POST -F token="xxx" -F ref="myTag" <a href="https://gitlab.com/api/v4/projects/12345678/trigger/pipeline" rel="noreferrer">https://gitlab.com/api/v4/projects/12345678/trigger/pipeline</a></p>