docs: Prepare for new sub tree

See #11925

docs/content/en/methods/menu-entry/_common/pre-post.md

@@ -1,39 +0,0 @@
----
-# Do not remove front matter.
----
-
-In this site configuration we enable rendering of [emoji shortcodes], and add emoji shortcodes before (pre) and after (post) each menu entry:
-
-{{< code-toggle file=hugo >}}
-enableEmoji = true
-
-[[menus.main]]
-name = 'About'
-pageRef = '/about'
-post = ':point_left:'
-pre = ':point_right:'
-weight = 10
-
-[[menus.main]]
-name = 'Contact'
-pageRef = '/contact'
-post = ':arrow_left:'
-pre = ':arrow_right:'
-weight = 20
-{{< /code-toggle >}}
-
-To render the menu:
-
-```go-html-template
-<ul>
-  {{ range .Site.Menus.main }}
-    <li>
-      {{ .Pre | markdownify }}
-      <a href="{{ .URL }}">{{ .Name }}</a>
-      {{ .Post | markdownify }}
-    </li>
-  {{ end }}
-</ul>
-```
-
-[emoji shortcodes]: /quick-reference/emojis/