Docker in the frontend

[Marie000]

I haven't had time to get started with docker on the frontend.

Some questions / concerns:

• the frontend currently runs on Node 14. It is a problem with some of the dependencies. I will be taking a look at that again later, but for now, we can just keep it on 14.
• the frontend needs to have access to the cache on redis. I did add redis to the API docker compose but I now realize it wouldn't be available to the frontend. We could keep using the external redis service for now. In the future, it might be interesting to have the frontend and API in the same codebase. Or do you have a suggestion on how to best handle that?

[Marie000]

We should be able to: run the frontend locally by starting a docker container, given that we have the .env file run the frontend on digitalOcean (no need to move it to DigitalOcean yet. And I assume if things work locally it should work on DigitalOcean, right?) once the API can also be run on a docker container, the front-end and back-end containers should work together.