Ensure sys.stdout has an istty method

lib/ansible/runner/__init__.py

@@ -745,6 +745,7 @@ class Runner(object):
             data = result.result
 
             # https://github.com/ansible/ansible/issues/4958
+            if hasattr(sys.stdout, "isatty"):
                 if "stdout" in data and sys.stdout.isatty():
                     if not string_functions.isprintable(data['stdout']):
                         data['stdout'] = ''