VSTS supports "Pull Request Iteration Statuses", i. e. the status of a pull-request iteration.
In my understanding, the benefit of using this is, that a status policy can be proactively enforced by VSTS.
1. push a new commit on a VSTS pull-request
2. Web-hook does not trigger Jenkins for some reason
3. pull-request stays valid even though not being built/tested
Link to VSTS API Documentation: https://docs.microsoft.com/en-us/rest/api/vsts/git/pull%20request%20iteration%20statuses?view=vsts-rest-4.1