Provide an ability to output what has happened during a passing test

[ben-walsh]

During PD it can be very helpful to see what happens with a test when it passes, particularly when wanting to compare differing passing/failing between different JVMs, JDK levels etc ...
Currently, the framework only outputs from failing tests.

The following "hack" was utilised during such PD efforts with a load test recently ...

diff --git a/stf.load/src/stf.load/net/adoptopenjdk/loadTest/LoadTestRunner.java b/stf.load/src/stf.load/net/adoptopenjdk/loadTest/LoadTestRunner.java
index 6acc040..e46286c 100644
--- a/stf.load/src/stf.load/net/adoptopenjdk/loadTest/LoadTestRunner.java
+++ b/stf.load/src/stf.load/net/adoptopenjdk/loadTest/LoadTestRunner.java
@@ -201,6 +201,9 @@ class LoadTestRunner {
                                                                // Keep in-memory count of pass/fail result
                                                                if (testPassed) {
                                                                        numberPassingTests.incrementAndGet();
+                                                                       originalSystemOut.println("BW PASSING TEST >");
+                                                                       originalSystemOut.println(new String(executionTracker.getCapturedOutput().toByteArray()));
+                                                                       originalSystemOut.println("< BW PASSING TEST");
                                                                } else {
                                                                        // Produce java dumps for only the first test failure if flag for creating dump is set by user
                                                                        long failureNum = numberFailingTests.incrementAndGet();
@@ -418,4 +421,4 @@ class LoadTestRunner {
                
                return total;
        }
-}
\ No newline at end of file
+}

This should be generalised, as necessary for non-load runner testing, and formalised so that it can be controlled through parameters or similar.