👷 Tweak generate client to error out if there are errors (#1377)

Author: tiangolo

.github/workflows/generate-client.yml

@@ -54,4 +54,4 @@ jobs:
     - name: Check changes
       if: ( github.event_name == 'pull_request' && github.secret_source != 'Actions' )
       run: |
-        git diff --staged --quiet || echo "Changes detected in generated client, run scripts/generate-client.sh and commit the changes"
+        git diff --staged --quiet || (echo "Changes detected in generated client, run scripts/generate-client.sh and commit the changes" && exit 1)