Fix incorrect version in CONTRIBUTING.md build bump example

Co-authored-by: bact <128572+bact@users.noreply.github.com>

Author: Copilot

CONTRIBUTING.md

@@ -181,7 +181,7 @@ This will create distribution packages in the `dist/` directory.
   #current_version = 2.4.0-dev0
 
   bump-my-version bump build
-  #current_version = 2.3.1-dev1
+  #current_version = 2.4.0-dev1
 
   bump-my-version bump major
   #current_version = 3.0.0-dev0