I am working on replacing Commons HTTPClient 3.x in Jenkins core in order to get new API features. I discovered that Maven Plugin HPI includes this library as well. It comes as a transient dependency from the Maven Interceptors set of Libraries (in particular, https://github.com/jenkinsci/maven-interceptors/tree/master/maven-agent). From what we see, this library is actually not used in the plugin at all, so I propose to just delete it.