conditionally auto commit badges

Author: fluentfuture

.github/workflows/ci.yaml

@@ -85,6 +85,9 @@ jobs:
             git config --global user.name 'github-actions'
             git config --global user.email '41898282+github-actions[bot]@users.noreply.github.com'
             git add *.svg
-            git commit -m "Autogenerated JaCoCo coverage badge"
-            git push
+            git add *.json
+            if ! git diff --cached --quiet; then
+              git commit -m "Update coverage badges for all modules"
+              git push
+            fi
           fi