lxc_container: fix lxc argument when executing lxc command

lxc_container fails when executing the lxc command (e.g. when creating
a new container) because PR#5358 broke the module argument
parsing. The resulting argument dict contained only the module argument name
and the argument flag but not the value. E.g.
```
- lxc_container:
    template: debian
```
would result in lxc command arguments `lxc template --template` instead of
`lxc --template debian`.

Fixes: 6f88426 ("lxc_container: minor refactor (ansible-collections#5358)")
Fixes ansible-collections#5578

Signed-off-by: Alexander Couzens <lynxis@fe80.eu>

plugins/modules/lxc_container.py

@@ -677,7 +677,7 @@ def _get_vars(self, variables):
 
         false_values = BOOLEANS_FALSE.union([None, ''])
         result = dict(
-            (k, v)
+            (v, self.module.params[k])
             for k, v in variables.items()
             if self.module.params[k] not in false_values
         )