title: Add comment to Github pull request from Jenkins pipeline
body: <p>I am wondering if there is already a way to update a Github (Enterprise) pull request with a comment within the Jenkins Pipeline syntax. I have it already updating it with the build status of success or failed automatically but I also want to post a comment with the test results and code coverage or the reason why the build failed. Before I start to write my own function in groovy calling the REST API of github to do this I wanted to make sure there wasn't already an easier way say like a plugin that had this function. </p>