Revert "[JENKINS-17337] Added test for NPE.(cherry picked from commit 1bf958af)"

This reverts commit 18b5f4f1.
It looks like this change depends on other test harness related changes.
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[JENKINS-17337] Added test for NPE.(cherry picked from commit 1bf958af)

[FIXED JENKINS-3265] Hotfix for regression in matrix project loading from 25084f52.(cherry picked from commit 3370e6ed)

updated online help for concurrent builds

added to online help about concurrent builds: a paragraph about using the hudson.slaves.WorkspaceList system property for configuring the separator

[FIXED JENKINS-17331] PerJobLocalRepositoryLocator should prefer the MavenModuleSetBuild.workspace for single-module builds.

[FIXED JENKINS-17084] Changelog should produce output even if some chang...

[FIXED JENKINS-17128] Unquote labels before processing

Also take advantage of JUnit’s ability to show the exact spot of a mismatch between two strings.