slash-commands-example: Fix numbering in README (#17452)

This PR fixes the numbering in the README for the
`slash-commands-example` extension.

Release Notes:

- N/A

Marshall Bowers committed 2y ago

7c9abcfd6c50640f04487e35cc7aa91cf9ceebd4

Parent: e5858c8

Committed by GitHub <noreply@github.com> on 9/5/2024, 7:39:09 PM