docs: fix code formatting in linger example

docs/recipes-rootless-podman.md

@@ -57,7 +57,7 @@ In order for user services to be started without an active login session,
 lingering needs to be enabled. This can be done by making sure a file for the
 Linux user exists in systemd's *linger* directory:
 
-```yaml
+```python
 storage.files[0].path: /var/lib/systemd/linger/myuser
 ```