fix syntax error in deploy-docs condition

Author: apache-hb

.github/workflows/docs.yaml

@@ -33,7 +33,7 @@ jobs:
 
   deploy-docs:
     name: Deploy Documentation to GitHub Pages
-    # if: github.event_name == 'push' && (contains(github.ref, '/heads/master')
+    if: github.event_name == 'push' && contains(github.ref, '/heads/master')
     needs: doxygen-docs
     runs-on: ubuntu-latest
     steps: