Related to JENKINS-42234 as it was causing the triggering
multibranch pipeline job notified by stash, mutliple job/projects build
Missing guard call to isMatch when processing update events
Git plugin 3.1.0 released on 4 Mar 2017 includes this change.
Code changed in jenkins
User: Stephen Connolly
[FIXED JENKINS-42236] Replicate the isMatch guard in heads