Fix synchronize retries (#18535)

* Fix synchronize retries

The synchronize module munges its task args on every invocation of
run(). This was problematic because the munged data was not fit for use
by a second pass of the synchronize module. Correct this by using a copy
of the task args on every invocation of run() so that the original args
are not affected.

Local testing using this playbook seems to confirm that things work as
expected:

  - hosts: all
  tasks:
    - delay: 2
      register: task_result
      retries: 1
      until: task_result.rc == 0
      synchronize:
        dest: /tmp/out
        mode: pull
        src: /tmp/nonexistent/

fixes #18281

* Update synchroncization fixture assertions

When we started operating on a copy of the task args the test assertions
were no longer asserting things about the munged state but of the
pristine state. Convert the copy of task args to a class member so that
it can be compared against later in testing and update the assertions to
check this munged copy.
* Shuffle objects around for cleaner testing

Attach the temporary args dict to the task rather than the action as
this makes updating the existing tests cleaner.

test/units/plugins/action/test_synchronize.py

@@ -99,11 +99,12 @@ class SynchronizeTester(object):
     execute_called = False
 
 
-    def _execute_module(self, module_name, task_vars=None):
+    def _execute_module(self, module_name, module_args=None, task_vars=None):
         self.execute_called = True
+        self.final_module_args = module_args
         self.final_task_vars = task_vars
         return {}
-    
+
     def runtest(self, fixturepath='fixtures/synchronize/basic'):
 
         metapath = os.path.join(fixturepath, 'meta.yaml')