Verify Gradle wrapper files were generated

.github/workflows/gradle-build.yml

@@ -12,6 +12,7 @@ jobs:
           arguments: wrapper
       - run: >
           if [[ -n $(git status --porcelain) ]]; then 
+            echo "Gradle wrapper files have not been updated."
             echo "Please run Gradle wrapper task and commit wrapper changes."
             exit 1
           fi