content: Replace calls to the code shortcode with fenced code blocks

content/en/functions/transform/XMLEscape.md

@@ -32,9 +32,9 @@ For example:
 
 When using `transform.XMLEscape` in a template rendered by Go's [html/template] package, declare the string to be safe HTML to avoid double escaping. For example, in an RSS template:
 
-{{< code file=layouts/_default/rss.xml >}}
+```xml {file="layouts/_default/rss.xml"}
 <description>{{ .Summary | transform.XMLEscape | safeHTML }}</description>
-{{< /code >}}
+```
 
 [disallowed characters]: https://www.w3.org/TR/xml/#charsets
 [html entities]: https://developer.mozilla.org/en-us/docs/glossary/entity