Make sure service_worker.js gets served via Pages

.gitlab-ci.yml

 pages:
   stage: deploy
   script:
-  # Evidently it's faster to copy everything and delete what we don't need 
+  # Evidently it's faster to copy everything and delete what we don't need
   # than it is to just copy what we need...
   - mkdir .public
-  - cp -r css fonts img js player opponents index.html config.xml .public
+  - cp -r css fonts img js player opponents index.html config.xml service_worker.js .public
   - find .public/opponents -type f ! \( -iname "*.png" -o -iname "*.gif" -o -iname "*.jpg" -o -iname "*.xml" \) -delete
   - mv .public public
   artifacts: