docs: Prepare for new sub tree

See #11925

docs/content/en/functions/strings/TrimLeft.md

@@ -1,28 +0,0 @@
----
-title: strings.TrimLeft
-description: Returns the given string, removing leading characters specified in the cutset.
-categories: []
-keywords: []
-action:
-  aliases: []
-  related:
-    - functions/strings/Chomp
-    - functions/strings/Trim
-    - functions/strings/TrimPrefix
-    - functions/strings/TrimRight
-    - functions/strings/TrimSuffix
-  returnType: string
-  signatures: [strings.TrimLeft CUTSET STRING]
-aliases: [/functions/strings.trimleft]
----
-
-```go-html-template
-{{ strings.TrimLeft "a" "abba" }} → bba
-```
-
-The `strings.TrimLeft` function converts the arguments to strings if possible:
-
-```go-html-template
-{{ strings.TrimLeft 21 12345 }} → 345 (string)
-{{ strings.TrimLeft "rt" true }} → ue
-```