docs: Prepare for new sub tree

See #11925

docs/content/en/hugo-pipes/bundling.md

@@ -1,26 +0,0 @@
----
-title: Concat
-linkTitle: Concatenating assets
-description: Bundle any number of assets into one resource.
-categories: [asset management]
-keywords: []
-menu:
-  docs:
-    parent: hugo-pipes
-    weight: 90
-weight: 90
-action:
-  aliases: []
-  returnType: resource.Resource
-  signatures: ['resources.Concat TARGETPATH [RESOURCE...]']
----
-
-## Usage
-
-Asset files of the same MIME type can be bundled into one resource using `resources.Concat` which takes two arguments, the target path for the created resource bundle and a slice of resource objects to be concatenated.
-
-```go-html-template
-{{ $plugins := resources.Get "js/plugins.js" }}
-{{ $global := resources.Get "js/global.js" }}
-{{ $js := slice $plugins $global | resources.Concat "js/bundle.js" }}
-```