Remove Google apt source from gitlab:assets:compile step

Chrome is already installed in this image, and the apt-get update
is only used to install jq.

.gitlab/ci/frontend.gitlab-ci.yml

@@ -38,6 +38,7 @@ gitlab:assets:compile:
     - bundle exec rake gitlab:assets:compile
     - time scripts/build_assets_image
     - scripts/clean-old-cached-assets
+    - rm -f /etc/apt/sources.list.d/google*.list # We don't need to update Chrome here
     # Play dependent manual jobs
     - install_api_client_dependencies_with_apt
     - play_job "review-build-cng" || true # this job might not exist so ignore the failure if it cannot be played