[3.11] gh-107755: Document the correct default value of slice step (GH-107756) (#108956)

gh-107755: Document the correct default value of slice step (GH-107756)

Document the correct default value of slice step.
(cherry picked from commit 9bf350b0662fcf1a8b43b9293e6c8ecf3c711561)

Co-authored-by: wim glenn <hey@wimglenn.com>