Avoid streaming to 2 similar OutputStreams

[yahavi]

I have an issue when running launcher.launch().stdout(listener) from a different plugin.

Background:
ContainerExecDecorator decorates the launcher.

The issue:
ContainerExecDecorator's doLaunch() gets an OutputStream and splits the output to both the OutputStream and launcher's logger. In my case, OutputStream and and launcher's logger are the same.
Expected: All lines printed properly in job's log
Actual: Lines are printed twice in job's log

Reconstruction:
Run this line inside a pod:

container('maven') {
    rtMaven.run pom: 'maven-example/pom.xml', goals: 'clean install', buildInfo: buildInfo
}