Fine logging with stack trace when queue item cancelled

[jglick]

Hoping to track down a test failure in @cloudbees which shows a build being aborted with QueueTaskCancelled but not why. The other plausible path is

workflow-durable-task-step-plugin/src/main/java/org/jenkinsci/plugins/workflow/support/steps/ExecutorStepDynamicContext.java

Lines 113 to 115 in 68be217

	} catch (CancellationException x) {
	LOGGER.log(Level.FINE, "ceased to wait for " + node, x);
	throw new FlowInterruptedException(Result.ABORTED, /* TODO false probably more appropriate */true, new ExecutorStepExecution.QueueTaskCancelled());

which already does fine logging.