doc: add note about latest GitHub release

Refs: https://github.blog/changelog/2022-10-21-explicitly-set-the-latest-release/
PR-URL: #45111
Reviewed-By: Richard Lau <rlau@redhat.com>
Reviewed-By: Rafael Gonzaga <rafael.nunu@hotmail.com>
Reviewed-By: Ruy Adorno <ruyadorno@google.com>
Reviewed-By: Rich Trott <rtrott@gmail.com>
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Luigi Pinca <luigipinca@gmail.com>
Reviewed-By: Michael Dawson <midawson@redhat.com>

doc/contributing/releases.md

@@ -903,6 +903,8 @@ This script will use the promoted builds and changelog to generate the post. Run
 * Select the tag version you pushed earlier.
 * For release title, copy the title from the changelog.
 * For the description, copy the rest of the changelog entry.
+* If you are not releasing the latest "Current", uncheck
+  "Set as the latest release".
 * Click on the "Publish release" button.
 
 ### 19. Cleanup