Moved the _inventory.clear_group_dict_cache() from creating a group w… (#17766)

* Moved the _inventory.clear_group_dict_cache() from creating a group which doesn't exist, to adding members to the group.

* Update __init__.py

Update to use changed: block to catch all changes for cache clear as suggested

lib/ansible/plugins/strategy/__init__.py

@@ -624,9 +624,6 @@ class StrategyBase:
         group_name = result_item.get('add_group')
         new_group = self._inventory.get_group(group_name)
         if not new_group:
-            # clear cache of group dict, which is used in magic host variables
-            self._inventory.clear_group_dict_cache()
-
             # create the new group and add it to inventory
             new_group = Group(name=group_name)
             self._inventory.add_group(new_group)
@@ -641,6 +638,10 @@ class StrategyBase:
             new_group.add_host(real_host)
             changed = True
             
+        if changed:
+            # clear cache of group dict, which is used in magic host variables
+            self._inventory.clear_group_dict_cache()
+
         return changed
 
     def _load_included_file(self, included_file, iterator, is_handler=False):