docs: Prepare for new sub tree

See #11925

docs/content/en/methods/time/Add.md

@@ -1,23 +0,0 @@
----
-title: Add
-description: Returns the given time plus the given duration.
-categories: []
-keywords: []
-action:
-  related:
-    - functions/time/AsTime
-    - functions/time/Duration
-    - functions/time/ParseDuration
-  returnType: time.Time
-  signatures: [TIME.Add DURATION]
----
-
-```go-html-template
-{{ $t := time.AsTime "2023-01-27T23:44:58-08:00" }}
-
-{{ $d1 = time.ParseDuration "3h20m10s" }}
-{{ $d2 = time.ParseDuration "-3h20m10s" }}
-
-{{ $t.Add $d1 }} → 2023-01-28 03:05:08 -0800 PST
-{{ $t.Add $d2 }} → 2023-01-27 20:24:48 -0800 PST
-```