chore: rename workflow to .yaml and improve CI log output

Author: jplbrun

.github/workflows/check-version-bump.yml .github/workflows/check-version-bump.yaml.github/workflows/check-version-bump.yml renamed to .github/workflows/check-version-bump.yaml

@@ -32,4 +32,6 @@ jobs:
             else
               echo "Version bump detected: $VERSION_BUMPED"
             fi
+          else
+            echo "No src/ changes. Version bump not required."
           fi