create config to build production docker

[rngadam]

• minimal Dockerfile for production container
• gunicorn configuration
• README.md container instructions for Azure and Google Cloud
• create LOUIS_DSN env variable to connect to database
• change blueprints mountpoints to be "" instead of "/" to prevent 308 redirects creating an unsecure https to http transition
• switch from psycopg2 to psycopg3
• don't dump the grants and owners in database dump to facilitate restore (references to vscode user)
• try to use az containerapp up (failing due to lack of rights on AAD
• add recommendations to app.py from Google examples
• try to isolate error between psycopg and Azure postgresql ssl connection to sample example