[BUG] Documentation error on document_lifecycle.md

[eusousu]

What is the bug?

The doc on guides/document_lifecycle.md states that you can get the response of client.indices.exists as a boolean value but it's a http response, to get the boolean value you need to unpack it's "body" field.

How can one reproduce the bug?

Execute the code on guides/document_lifecycle.md, it will never create an index as the truth value of a filled object is true so the creation will never happen.