When a PR is created by someone who doesn't have the write permission in a repository (not trusted author) then the plugin is using the `Jenkinsfile` from the trusted branch like `develop`

In that case we have a warning in the build logs like

Loading trusted files from base branch develop at XXXXX rather than XXXXX

When you build is generating more than few lines of logs you are 99.999999% sure to miss this message which is at the beginning of your logs and thus trying to understand why your build is failing because you changed something in the `Jenkinsfile` and it's not used is a nightmare

cc jglick, stephenconnolly, abayer