[JENKINS-26156] Calling BodyInvoker.withDisplayName(null) was always …

…a no-op, and will soon be a FindBugs warning.

(cherry picked from commit 7806a76)

src/main/java/org/jenkinsci/plugins/workflow/steps/CatchErrorStep.java

@@ -73,7 +73,6 @@ public DescriptorImpl() {
            StepContext context = getContext();
            context.newBodyInvoker()
                    .withCallback(new Callback())
                    .withDisplayName(null)
                    .start();
            return false;
        }

src/main/java/org/jenkinsci/plugins/workflow/steps/PushdStep.java

@@ -84,7 +84,6 @@ public DescriptorImpl() {
            listener.getLogger().println("Running in " + dir);
            body = getContext().newBodyInvoker()
                    .withContext(dir)
                    .withDisplayName(null)
                    // Could use a dedicated BodyExecutionCallback here if we wished to print a message at the end ("Returning to ${cwd}"):
                    .withCallback(BodyExecutionCallback.wrap(getContext()))
                    .start();

src/main/java/org/jenkinsci/plugins/workflow/steps/TimeoutStepExecution.java

@@ -25,7 +25,6 @@ public boolean start() throws Exception {
        StepContext context = getContext();
        body = context.newBodyInvoker()
                .withCallback(new Callback())
                .withDisplayName(null)  // hide the body block
                .start();
        long now = System.currentTimeMillis();
        end = now + step.getUnit().toMillis(step.getTime());