Revert debug in UncaughtExceptionsTest

Debug was added via
ibmruntimes/openj9-openjdk-jdk11#663

The debug isn't useful. Related to
eclipse-openj9/openj9#11930

Signed-off-by: Peter Shipton <Peter_Shipton@ca.ibm.com>

test/jdk/java/lang/Thread/UncaughtExceptionsTest.java

@@ -93,12 +93,7 @@ class UncaughtExitSimulator extends Thread implements Runnable {
 
  public static void throwRuntimeException() { throw new RuntimeException("simulateUncaughtExitEvent"); }
 
- public void run() {
- if (!Thread.currentThread().getName().equals("Thread-0")) {
- com.ibm.jvm.Dump.SystemDump();
- }
- throwRuntimeException();
- }
+ public void run() { throwRuntimeException(); }
 
  /**
  * A thread is never alive after you've join()ed it.