NPE Fix
java.lang.NullPointerException
	at org.jenkinsci.plugins.DistributedTests.TaskCoordinator.readTasks(TaskCoordinator.java:65)
 	at org.jenkinsci.plugins.DistributedTests.DistributedBuild$DistributedExecutor.doRun(DistributedBuild.java:173)
 	at hudson.model.AbstractBuild$AbstractBuildExecution.run(AbstractBuild.java:533)
 	at hudson.model.Run.execute(Run.java:1745)
 	at org.jenkinsci.plugins.DistributedTests.DistributedBuild.run(DistributedBuild.java:130)
 	at hudson.model.ResourceController.execute(ResourceController.java:89)
 	at hudson.model.Executor.run(Executor.java:240)
 	at hudson.model.OneOffExecutor.run(OneOffExecutor.java:43)