The env MEDIA_URL was missing in the frontend
Dockerfile. It is not necessary in our
running environment (staging / preprod ...) but it
is necessary if we want to run the frontend with
a different media url.
SW_DEACTIVATED was missing as well, we need to
deactivate the service worker in the frontend when
we test with Playwright.
Dockerize the frontend development environment
to make it easy to display the frontend
development environment in the browser.
We don't mix it with the command `make run` to
let it kind of optional to run the frontend
in a docker container. We let it optional because
the hot reload doesn't work well in the docker
container. The volume synch make it a bit slower
as well. So, we let the developer decide to run
the frontend in a docker container or not.
