docs: Prepare for new sub tree

See #11925

docs/content/en/methods/site/BaseURL.md

@@ -1,37 +0,0 @@
----
-title: BaseURL
-description: Returns the base URL as defined in the site configuration.
-categories: []
-keywords: []
-action:
-  related:
-    - functions/urls/AbsURL
-    - functions/urls/AbsLangURL
-    - functions/urls/RelURL
-    - functions/urls/RelLangURL
-  returnType: string
-  signatures: [SITE.BaseURL]
----
-
-Site configuration:
-
-{{< code-toggle file=hugo >}}
-baseURL = 'https://example.org/docs/'
-{{< /code-toggle >}}
-
-Template:
-
-```go-html-template
-{{ .Site.BaseURL }} → https://example.org/docs/
-```
-
-{{% note %}}
-There is almost never a good reason to use this method in your templates. Its usage tends to be fragile due to misconfiguration.
-
-Use the [`absURL`], [`absLangURL`], [`relURL`], or [`relLangURL`] functions instead.
-
-[`absURL`]: /functions/urls/absURL
-[`absLangURL`]: /functions/urls/absLangURL
-[`relURL`]: /functions/urls/relURL
-[`relLangURL`]: /functions/urls/relLangURL
-{{% /note %}}