title: Jenkins pipeline for merge request in Gitlab
body: <p>I've started lately to use Jenkins and i need some help with creating a pipeline.</p>
  
  <p>I want to create the following pipeline:
  For each merge request from develop to master in Gitlab, Trigger a Jenkins job that run an end-to-end test, And merge the branches in Gitlab only if the test succeeded.</p>
  
  <p>I have found the following article that gives me an explanation for most of the things that i need:
  <a href="https://vetlugin.wordpress.com/2017/01/31/guide-jenkins-pipeline-merge-requests/" rel="noreferrer">https://vetlugin.wordpress.com/2017/01/31/guide-jenkins-pipeline-merge-requests/</a></p>
  
  <p>I'm still looking for an answer for one question:
  How can Jenkins response to Gitlab with the result of the end-to-end test (Success/Fail), So Gitlab will know whether to merge to branches or not?</p>
  
  <p>Please advise,
  Thanks!</p>