docs: remove metadata section in documentation sicne it's autogenerated

docs/content/http.md

@@ -235,16 +235,6 @@ Properties:
 - Type:        string
 - Required:    false
 
-### Metadata
-
-Here are the possible system metadata items for the http backend.
-
-| Name | Help | Type | Example | Read Only |
-|------|------|------|---------|-----------|
-| content-disposition | Content-Disposition header | string | inline | N |
-
-See the [metadata](/docs/#metadata) docs for more info.
-
 ## Backend commands
 
 Here are the commands specific to the http backend.