dockerfile(docs): fix liquid syntax

Signed-off-by: CrazyMax <[email protected]>

Author: crazy-max

frontend/dockerfile/docs/reference.md

@@ -964,9 +964,11 @@ the most-recently-applied value overrides any previously-set value.
 To view an image's labels, use the `docker image inspect` command. You can use
 the `--format` option to show just the labels;
 
+{% raw %}
 ```console
 $ docker image inspect --format='{{json .Config.Labels}}' myimage
 ```
+{% endraw %}
 
 ```json
 {