Improve "body" argument document with a link to some api page

[dej611]

While many client methods offer an higher level API to interact with the request, but there's always the last resort body for the uncovered cases.
Now all definitions for the body argument are like the following:

body (Dict[str, Any] | None)

It would be helpful to point the user to the API page.
I know sometimes there's an API link before the actual API arguments list, but having it inline may be more practical, in particular for those APIs with a longer list of arguments.