[MM-13833] Configured unit tests to log through t.Log (#10272)

* Rerouted the unit test logs through t.Log

* resolving merge confilvts

* Update testing.go

* Update helper_test.go

* Added godocs for NewTestingLogger

* Added go docs for NewTestingLogger

* Resolving conflicts

app/diagnostics_test.go

@@ -57,7 +57,7 @@ func TestPluginActivated(t *testing.T) {
 }
 
 func TestDiagnostics(t *testing.T) {
-	th := Setup().InitBasic()
+	th := Setup(t).InitBasic()
 	defer th.TearDown()
 
 	if testing.Short() {