Update images, remove image build, improve CD

.gitlab-ci.yml

codehub/Chart.yaml

codehub/README.md

codehub/values.yaml

dockerfiles/browser/Dockerfile

dockerfiles/browser/supervisord.conf

dockerfiles/browser/ui.js

dockerfiles/code-server-anaconda/Dockerfile

dockerfiles/code-server-anaconda/docker-entrypoint.sh

dockerfiles/code-server-anaconda/install_tools.sh

dockerfiles/code-server/Dockerfile

dockerfiles/code-server/docker-entrypoint.sh

dockerfiles/code-server/install_tools.sh

dockerfiles/nginx/30-oauth.sh

dockerfiles/nginx/Dockerfile

dockerfiles/nginx/README.md

dockerfiles/nginx/nginx.conf

dockerfiles/oauth/Dockerfile

dockerfiles/oauth/app.py