Nope. Try again

For now, due to critical label, this will solve the issue for now.
Leaving us time to perform a proper refactor.

Refs idaholab#14512

python/TestHarness/testers/RunApp.py

@@ -260,10 +260,10 @@ def testExitCodes(self, moose_dir, options, output):
 
             if reason != '':
                 self.setStatus(self.fail, str(reason))
-                reason += "\n\nExit Code: " + str(self.exit_code)
+                return "\n\nExit Code: " + str(self.exit_code)
 
         # Return anything extra here that we want to tack onto the Output for when it gets printed later
-        return reason
+        return ''
 
     def processResults(self, moose_dir, options, output):
         """