Don't fail if no changelog changes need to be pushed

Fixes #8

Author: kzu

.github/workflows/changelog.yml

@@ -33,5 +33,4 @@ jobs:
           git config --local user.name github-actions
           git config --local user.email github-actions@github.com
           git add changelog.md
-          git commit -m "🖉 Update changelog with ${GITHUB_REF#refs/*/}"
-          git push
+          (git commit -m "🖉 Update changelog with ${GITHUB_REF#refs/*/}" && git push) || echo "Done"