Add support for a new SENTRY_RELEASE and SENTRY_ENVIRONMENT env.
It is optional and allows to init sentry with a Release version and an
env (used internally at Twenty).
Docker image have been updated do intergrate the new env as an Argument
Having 2 different dev setups caused confusion, let's remove the Docker
local setup and recommend people install yarn locally.
Also simplified some docs by merging pages together, the recommend
self-hosting option is now the docker-compose / to adapt the
docker-compose.
