... hudson.ExtensionFinder$Sezpoz scout
WARNING: Failed to scout jenkins.plugin.mockloadbuilder.MatrixMockProjectFactory
java.lang.NoClassDefFoundError: hudson/matrix/MatrixProject
	at java.lang.Class.forName0(Native Method)
	at java.lang.Class.forName(Class.java:348)
	at hudson.ExtensionFinder$Sezpoz.scout(ExtensionFinder.java:669)
	at hudson.ClassicPluginStrategy.findComponents(ClassicPluginStrategy.java:473)
	at hudson.ExtensionList.load(ExtensionList.java:365)
	at hudson.ExtensionList.ensureLoaded(ExtensionList.java:303)
	at hudson.ExtensionList.getComponents(ExtensionList.java:168)
	at jenkins.model.Jenkins$8.onInitMilestoneAttained(Jenkins.java:1104)
	at jenkins.InitReactorRunner$1.onAttained(InitReactorRunner.java:82)
	at org.jvnet.hudson.reactor.ReactorListener$Aggregator.onAttained(ReactorListener.java:104)
	at org.jvnet.hudson.reactor.Reactor$1.run(Reactor.java:176)
	at org.jvnet.hudson.reactor.Reactor$Node.run(Reactor.java:117)
	at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
	at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
	at java.lang.Thread.run(Thread.java:748)
Caused by: java.lang.ClassNotFoundException: hudson.matrix.MatrixProject
	at jenkins.util.AntClassLoader.findClassInComponents(AntClassLoader.java:1374)
	at jenkins.util.AntClassLoader.findClass(AntClassLoader.java:1327)
	at jenkins.util.AntClassLoader.loadClass(AntClassLoader.java:1080)
	at java.lang.ClassLoader.loadClass(ClassLoader.java:357)
	... 15 more