Fix CI not setting the job as failed when connector validation finds violations

Author: surister

.github/workflows/main.yml

@@ -47,6 +47,11 @@ jobs:
         run: |
           source ./.venv/bin/activate
           python -m connector_packager.package --validate-only $GITHUB_WORKSPACE/cratedb-tableau-connector/cratedb_jdbc
+          
+          cat packaging_logs.txt
+          
+          # If validation fails, stop the job.
+          grep 'Validation succeeded' packaging_logs.txt
 
       - name: Build connector
         if: ${{ github.event_name == 'release' }}