Fix Ansible 2.7 uri module

The 'path' argument doesn't exist, but 'src' and 'dest' do.

Currently this fails due to a KeyError if the module is used.

Also, fix the test case to use the 'dest' attribute which is
what all versions of the module actually use, rather than
'path'.

Change-Id: I09ec78ec16beb455338cf311fc4a9d23442071ab

tests/fixtures/config/ansible/git/org_plugin-project/playbooks/uri_bad_path.yaml

@@ -3,4 +3,4 @@
     - uri:
         method: GET
         url: https://example.com
-        path: /tmp/example.out
+        dest: /tmp/example.out

zuul/ansible/base/action/uri.py

@@ -30,6 +30,9 @@ class ActionModule(uri.ActionModule):
             return paths._fail_module_dict(self._task.action)
 
         if paths._is_localhost_task(self):
-            paths._fail_if_unsafe(self._task.args['path'])
+            for arg in ('src', 'dest'):
+                dest = self._task.args.get(arg)
+                if dest:
+                    paths._fail_if_unsafe(dest)
 
         return super(ActionModule, self).run(tmp, task_vars)