ci: handle no changes gracefully

Author: gadenbuie

.github/workflows/build-docs.yml

@@ -55,6 +55,5 @@ jobs:
       run: |
         git config --global user.name "$GITHUB_ACTOR"
         git config --global user.email "$GITHUB_ACTOR@users.noreply.github.com"
-        git add docs/
-        git commit -m "ci(docs): Automated site build"
-        git push
+        git add docs/ && git commit -m "ci(docs): Automated site build" || echo "No doc changes"
+        git push || echo "No doc updates to push"