Update git index to make git diff-index behave as expected (#5)

Source-Version: bbfe0b077c7179ef35139cc6629ecb4fee4ff494

.github/workflows/update-readme.yml

@@ -18,7 +18,7 @@ jobs:
           rm -f latest 2>/dev/null || true
           ln -s "./${LATEST_VERSION}/" latest
           git add latest
-          if git diff-index --quiet HEAD ; then
+          if git diff --quiet HEAD; then
             echo "No updates."
           else
             echo "Updated README and latest symlink"